Funding for the Clement Park memorial met unforeseen resistance. It was budgeted at $2.5 million, less than the library project, which the families had raised in four months. This one looked easy.

But by the time they started fund-raising in 2000, goodwill had been tapped out. They scaled back the project by a million in 2005. Still, they were not even close.

Bill Clinton had taken a personal interest in the massacre as president. He returned to Jeffco in July 2004 to rev up support. He brought in $300,000. That was a big boost, but momentum fizzled again.

Before he retired, Supervisory Special Agent Fuselier requested permission from the head of his branch to share his analysis. His boss agreed. Other experts brought in by the FBI cooperated as well, including Dr. Hare, Dr. Frank Ochberg, and others who spoke off the record. On the fifth anniversary of the massacre, a summary of their analysis was published.

New York Times columnist David Brooks devoted an op-ed piece to the team's conclusions. Tom Klebold read it. He didn't like it. He sent David Brooks an e-mail saying so. Brooks was struck by how loyal Tom still felt toward Dylan. After several exchanges, Tom and Sue agreed to sit down with Brooks to discuss their boy and his tragedy--the first and only media interview any of the four parents has ever given. columnist David Brooks devoted an op-ed piece to the team's conclusions. Tom Klebold read it. He didn't like it. He sent David Brooks an e-mail saying so. Brooks was struck by how loyal Tom still felt toward Dylan. After several exchanges, Tom and Sue agreed to sit down with Brooks to discuss their boy and his tragedy--the first and only media interview any of the four parents has ever given.

It turned out that they were kind of angry, too. Sue recounted an incident where she was offered absolution. "I forgive you for what you've done," the person said. That infuriated Sue. "I haven't done anything for which I need forgiveness," she told Brooks.

But mostly Tom and Sue were bewildered. They were convinced that jocks and bullying had been behind it, but jocks and bullies are everywhere and few kids are trying to blow up their high school. They were bright people, and they knew they weren't qualified to offer an explanation for their son's crimes. "I'm a quantitative person," Tom said. He was a scientist and a businessman. "We're not qualified to sort this out," he said.

They had run it over and over in their heads; they had tried to be objective, and they could honestly say they could rule one cause out. "Dylan did not do this because of the way he was raised," Susan said. They were emphatic about that. "He did it in contradiction to the way he was raised."

They were aware the public had reached a different verdict: the primary culprits were them. When Brooks met them, Tom had a stack of news stories documenting their poll numbers: 83 percent blamed the two of them and Eric's parents. In five years, the figure had barely budged. For the Klebolds, judgment was the price of silence. And it stung.

The public condemned them, but those close to the family did not. "Most people have been good-hearted," Tom said.

He and Sue accepted responsibility for one tragic mistake. Dylan was in agony; they'd thought he would be just fine. "He was hopeless," Tom said now. "We didn't realize it until after the end." They had not induced Dylan's homicide, they believed, but failed to prevent his suicide. They failed to see it coming. "I think he suffered horribly before he died," Sue said. "For not seeing that, I will never forgive myself."

Tom and Sue preferred to talk about Columbine as a suicide. "They acknowledge but do not emphasize the murders their son committed," Brooks wrote. What they really yearned for was an authoritative study that would explain why Eric and Dylan did it. Yet they had just read the analysis by some of the top experts in North America; they had dismissed it for providing the wrong explanation. They complained that Dr. Fuselier had assessed their son without interviewing them. Fuselier was dying to.

Mostly, the four parents remain a mystery. They have chosen that path. But David Brooks spent enough time with the Klebolds to form a distinct impression, and he has proven himself a good judge of character. He concluded his column with this assessment: Dylan left Tom and Sue to face terrible consequences. "I'd say they are facing them bravely and honorably."

The Klebolds wanted to understand what happened. They wanted to help other parents like them. They did not feel safe talking to the press, but they talked to a pair of child psychologists, under the condition that they not cite them directly. They were writing a book about teen violence. The problem was that at the time they published, the authors had no access to the crucial evidence.

Patrick Ireland slips his right foot into a hard plastic brace every morning as he gets dressed. He twists open a prescription bottle and swallows a dose of antiseizure meds. He walks with a limp. His mind is sharp, but he hesitates occasionally to find the words. His friends don't notice. He knows. It's not quite like before.

Patrick rarely thinks about before. Life is different than he imagined before. Better. Shoes are an issue, because of the brace. And his big toe is crooked inward, scrunches the others over. The little toe on his right foot sticks way out--nobody makes a shoe that wide. The doctors never set his foot right. "My dad's pretty pissed off," he said.

He still hangs out with many of his high school buddies. They don't talk about the massacre much, which is what many of the survivors report. It isn't emotional anymore, just boring. They're done.

He is tired of interviews, too. Occasionally he agrees to one. Reporters generally approach the library ordeal gingerly, but Patrick just plunges in, describing it unemotionally, as if recapping a movie. When he did Oprah's show, she played a clip of him going out the window.

"Whoa!" she said. "So is it difficult for you to see that video?"

"No."

"It's not? OK."

He felt good watching it, actually. He felt a sense of accomplishment.

Patrick got a perplexing voice mail one morning in the spring of 2005. It was an old friend he hadn't heard from in a while, wishing him well "today," hoping he was all right. Huh. Now, what could that mean? Huh. Now, what could that mean?

That afternoon, Patrick dated a document at work: April 20. Was it anniversary time already again? Was it anniversary time already again?

Linda Sanders felt every anniversary. Her mood began to sour each April; she got jittery, she could feel it coming.

She tried dating; that was impossible. Dave lingered, and men resented his presence. He was a national hero--who could compete with that?

"It's, like, Top Dave Sanders Top Dave Sanders," she said. "It's not fair to another man to be compared to the man I've built. He's so high on a pedestal he's in heaven."

She knew Dave would have wanted her to find someone. She pictured him up there saying, "Linda, I want somebody to hug you."

"It's impossible," Linda said. "There's nobody coming. I'm destined to be alone because of the way he left."

Linda withdrew. She stopped answering the door, stopped answering the phone. For two years she hardly spoke at all. She sedated herself with Valium and alcohol. "I was like a vacant person," she said, "going through the motions of life. I'd go to the store, I was going places, but I was empty."

Her father worried. What could he do?

"I want my Linda back," he said.

Linda never went back to work. She walks every day, and she looks after her parents. She does not go near the Columbine Lounge--too many memories, and too close to alcohol. She can't watch movies with guns in them or read thrillers.

One of those Aprils, years after getting sober, she felt a sudden, desperate need for help. "I ran out the front door and I looked for any neighbor that was home," she said. "I needed a hug, you know, I needed a hug. So I knocked on my neighbor's door, she wasn't home, so I went to my next neighbor, she was home. I walked in and she was reading a book. 'You're it,' I said. And I can't remember her name. I said I needed a hug. She looked at me and I was crying and she said OK. She gave me a hug."

Linda still gets letters now and then from strangers who hear Dave's story or hers and sense immediately how it was for Linda. Most people don't. Most people see kids and they see parents. Every once in a while, someone gets how it was for the wife. A woman wrote to tell Linda she understood. "That letter came on a real bad day," Linda said. "And it carried me. I hold that letter every night. That woman has no idea what she did for me."

Several survivors published memoirs, and Brooks Brown wrote his take on the killers and his ordeal. None garnered a fraction of the attention of Misty Bernall's book.

In September 2003, the last known layer of the cover-up finally came out. It had unraveled over the course of a full year. It started when someone in the sheriff's department found some paperwork in a three-ring binder unrelated to the Columbine case. It was a brief police report on Eric Harris. Eight pages from his Web site were attached. They included the "I HATE" rants, boasts about the missions, and descriptions of the first pipe bombs. Eric bragged about detonating one. The report was dated August 7, 1997, more than six months earlier than reports uncovered to date.

The report was brought to the new Jeffco sheriff, Ted Mink. He called a press conference. "This discovery and its implications are upsetting," he said. "The obvious implication... is that the sheriff's office had some knowledge of Eric Harris's and Dylan Klebold's activities in the years prior to the Columbine shootings." He released the documents and asked Colorado Attorney General Ken Salazar to conduct an outside investigation.

Salazar assigned a team, which discovered that more crucial documents were missing. Much of Mike Guerra's file related to his premassacre investigation had disappeared--both the physical and electronic copies. In February 2004, the attorney general issued a report stating that Jeffco was not negligent, but should have followed through with the warrant and searched Eric's house more than a year before Columbine. It also said files were still missing.

His team continued investigating. Some people refused to cooperate. The interview report on former sheriff John Stone stated that he was visibly angry and considered the investigation politically motivated. "We were unable to ask Stone any questions or have any meaningful dialogue regarding our investigation due his apparent state of agitation," it concluded.

The breakthrough came a month later, when investigators went back for a third interview with Guerra. This time, he was more forthcoming. He spilled the one secret Jeffco officials had been good at keeping: the existence of the Open Space meeting. Investigators quietly began confronting other officials who had attended. They got some colorful responses. Former undersheriff John Dunaway said he believed Guerra was upset that "he might be viewed as some kind of blithering idiot. That he, you know, was sitting on top of all of this."

In August 2004, the Colorado attorney general called a grand jury to flush the file out and consider indictments. The panel swore in eleven witnesses. The file was never recovered, though investigators were able to reconstruct most of it.

The probe turned up other startling discoveries. According to the grand jury report, Division Chief John Kiekbusch's assistant, Judy Searle, testified that in September 1999, he asked her to find the Guerra file. He told her to search the computer network and the physical files, and to do it in secret. He instructed her specifically not to tell the officers involved. Searle testified under oath that she found that suspicious. She normally would have started her search by talking to those officers. Searle searched, and discovered nothing. She gave Kiekbusch the news: there seemed to be no record anywhere, no sign the file ever existed. She watched his reaction. She testified that he appeared "somewhat relieved."

According to that same report, in 2000, Kiekbusch instructed her to shred a large pile of Columbine reports. Searle testified that she did not find the request unusual at the time, because Kiekbusch was preparing to leave the office, and Searle assumed he was purging duplicates. She complied.

The grand jury released its report on September 16, 2004. It found that the Guerra file should have been stored in three separate locations, both physical and electronic. All three were destroyed, it concluded--lapparently during the summer of 1999. It described that as "troubling."

It was also disturbed by attempts to suppress the information--specifically, the Open Space meeting, attended by Stone, Dunaway, Kiekbusch, Thomas, Guerra, and the county attorney, among others. "The topic of the Open Space meeting, the press conference omissions and the actions of Lt. Kiekbusch raise suspicions to the grand jury about the potential that the files were deliberately destroyed," its report stated.

But every witness denied involvement in the destruction, the report said. Given that, the grand jury could not determine whether the suspicious activity "is tied to a particular person or the result of a particular crime." Accordingly, it concluded that there was insufficient evidence to indict.

Kiekbusch filed a formal objection. He said the shredding was limited to drafts or copies. His assistant's perception of his relief was a mystery to him.

He said the grand jury implied that he had attempted to cover up, hide, or destroy documents. He unequivocally denied all of it.

Brian Rohrbough got most of what he sought: nearly all the evidence came out, and the national response protocol changed. But he never felt like he'd won. He gave up on justice. No one would pay; nothing would change.

Most of the top officials left the Jeffco sheriff's department. Stone survived the recall petition drive, but did not run for reelection. The one county official to come out of Columbine glowing was DA Dave Thomas. Many victims had perceived him as their champion. In 2004, he gave up his position to run for Congress. Polls indicated a toss-up, and the race gained national prominence and funding. The Open Space scandal broke less than two months before Election Day. Thomas's poll numbers plunged. Money dried up. He lost big. In 2007, he ran for school board. He now helps oversee 150 Jefferson county schools, including Columbine High.

Brian Rohrbough hurled himself into a different passion. He picketed abortion clinics and rose to president of Colorado Right to Life. There, he butted heads with the conservative parent organization, which he considered far too liberal. The last straw came when Rohrbough signed an open letter berating Christian conservative leader James Dobson as soft on abortion. It was published as a full-page newspaper ad. National Right to Life expelled his chapter. Dobson's organization, Focus on the Family, issued a news release calling it "a rogue and divisive group."

Later, Brian ran for office. He joined an obscure third party that got itself on the ballot in three states. It nominated Brian for vice president of the United States.

Brian wasn't always mad. He remarried and adopted two children, who gave him great comfort. At work, he could be surprisingly tranquil. He continued to run his custom audio business, doing most of the labor himself. He loved the precision work: tweaking the acoustic gauges, setting time delays for the front speakers just a fraction of an instant long, so the chords struck the driver's eardrum at precisely the same moment as the sound waves rolling in from the rear. Exquisite harmony. Brian could get lost for hours in his workshop. When a customer stopped by for a consultation, he was as gentle as Mr. Rogers buttoning up his cardigan.

Then he would think about Danny. Or a stray thought would lead him back to Columbine. The scowl returned.

Brad and Misty Bernall got out of Colorado. They moved to a hamlet called Blowing Rock, just off the Blue Ridge Parkway in the heart of the North Carolina mountains. They hated it out there. More isolation than they'd bargained for. Their marriage was shaky sometimes, but they held on. Nearly all the parents of the Thirteen stayed together.

Brad had struggled mightily in the early days, but as time wore on friends said he came to terms with Cassie's death. Misty smoldered. Nearly a decade later, friends described her as getting angry and frustrated at the mention of the martyr controversy. Misty felt she had been robbed, twice. Eric and Dylan took her daughter; journalists and detectives snatched away the miracle.

Mr. D found new ways to amuse his kids at school. For each homecoming assembly, he impersonated a celebrity. One year, the homecoming theme was Copacabana, and Mr. D strode out dressed as Barry Manilow, in a fluffy blond wig, white leisure suit, and Day-Glo Hawaiian shirt.

"Hey, Mr. D, nice shoes!" a girl yelled. He kicked his leg up to show off his four-inch platform heels. The kids ate it up. The assembly was standard high school: cheers, awards, a hands-free cake-eating contest, and a blindfolded obstacle course. Typical raucous confusion ruled the corridors before and after.

Every now and then, on a nice day, Mr. D wandered outside for serenity. The heavy door swung shut behind him, the bolt caught, and the frenzy of nervous energy ceased. It was so still. Each step, he could hear the grass squish beneath his shoes. A teacher strolled to her car in the distance. Her keys tingled--they could be dangling from his own hand. He made the short hike up Rebel Hill. The crosses were gone, their holes filled, but the grass had not grown back along the path.

At the top of the mesa, the back side of Rebel Hill was deserted. When he stopped there long enough, he would see the prairie dogs. At first there was no sign of them, no movement whatsoever, save the overgrown grasses bending softly to the breeze. After fifteen minutes of silence, they began to scurry about the clumps of mountain aster, foraging for food, socializing, grooming each other, fattening up for the winter. Six months after the tragedy, Mr. D had run into a Japanese film crew up there, enraptured by the charming rodents. The crew had come to shoot a documentary about the massacre; they had expected teen angst and American social Darwinism. They were seduced by the tranquillity--less than a hundred yards from the school. They shot hours of footage of the twelve-inch prairie dogs.

The Japanese crew saw this place somewhat differently than Americans did. Their depiction was by turns tumultuous, brutal, explosive, and serene.

School shooters faded as a national fear for a while. They worsened in Europe. They returned to the States in an uglier form in the fall of 2006, when a spate of adult killers realized that a school setting would reap attention. There were four shootings in a three-week span, beginning in late August 2006. The shooters used various tactics to resemble the Columbine killers, including trench coats and Web sites mentioning them by name. They appeared to see Eric and Dylan's legacy as a marketing opportunity. National attention focused on five girls killed in a one-room Amish school in Pennsylvania. But in Denver, the Platte Canyon shooting was particularly tough.

Platte Canyon High School was just one county over, and the police force so small that the Jeffco sheriff commanded the response team. It was a big national story for a few hours; then it was over. In Jeffco, it hit much harder. The Denver TV stations stayed live with the story all afternoon. Everyone was transfixed. This time it was a hostage standoff, and the SWAT team did rush the building. The gunman had only two girls left at that point. When the cops rushed in, he shot one in the head, then took care of himself. He died instantly, but the victim was medevaced out. The city watched her helicopter take off and land on the rooftop of St. Anthony's; then viewers waited, hoping, for two hours. Doctors held a press conference early in the evening. She'd never had a chance.

The next morning's Rocky Mountain News Rocky Mountain News was filled with photos eerily like April 20: survivors sobbing, praying, holding on tight. was filled with photos eerily like April 20: survivors sobbing, praying, holding on tight.

Bomb scares at Columbine spiked. The school was evacuated a few days later. Moms felt their muscles clench, bracing for the terrifying news. Some had almost forgotten Columbine, but their bodies remembered. In an instant, it was April 20 again. The danger passed in a few hours--it was only a prank. The anxiety lingered.

In the ten years after Columbine, more than eighty school shootings took place in the United States. The principals who survived--many were targeted--invariably found themselves in over their heads. Mr. D made himself available to all of them. Many accepted his offer. He spent hours every semester sharing what he had learned.

Those calls were hard. An e-mail he received that fall was worse. "Dear Principal," it said. "In a few hours you will probably hear about a school shooting in North Carolina. I am responsible for it. I remember Columbine. It is time the world remembered it. I am sorry. Goodbye."

It had been sent in the morning, but Mr. D didn't check e-mail for several hours. He called the cops immediately, and they sent word to the boy's high school. Too late. The nineteen-year-old had driven past his school and fired eight shots, injuring two superficially. Then police raided his home and found his father dead.

The shooter was apprehended and taken into court. He was asked why he was obsessed with Columbine. He said he didn't know.

School shooters were starting to feel like a threat again. But the real shocker came the following spring, at Virginia Tech. Seung-Hui Cho killed thirty-two people, plus himself, and injured seventeen. The press proclaimed it a new American record. They shuddered at the idea of turning school shootings into a competition, then awarded Cho the title.

Cho left a manifesto explaining his attack. It cited Eric and Dylan at least twice as inspiration. He'd looked up to them. He did not resemble them. Cho did not appear to enjoy his rampage. He did not expect to. He emptied his guns with a blank expression. He shared none of Eric or Dylan's bloodlust. The videos Cho left described himself himself as raped, crucified, impaled, and slashed ear to ear. Cho appears to have been severely mentally ill, fighting a powerful psychosis, possibly schizophrenia. Unlike the Columbine killers, he did not seem to be in touch with reality or comprehend what he was doing. He understood only that Eric and Dylan left an impression. as raped, crucified, impaled, and slashed ear to ear. Cho appears to have been severely mentally ill, fighting a powerful psychosis, possibly schizophrenia. Unlike the Columbine killers, he did not seem to be in touch with reality or comprehend what he was doing. He understood only that Eric and Dylan left an impression.

52. Quiet

The morning of the attack, Eric and Dylan shot a brief farewell video in Eric's basement. Eric directed. "Say it now," he said.

"Hey, Mom," Dylan said. "I gotta go. It's about a half an hour till Judgment Day. I just wanted to apologize to you guys for any crap this might instigate. Just know I'm going to a better place. I didn't like life too much, and I know I'll be happy wherever the fuck I go. So I'm gone. Good-bye. Reb..."

Eric handed him the camera. "Yeah.... Everyone I love, I'm really sorry about all this," Eric said. "I know my mom and dad will be just like... just fucking shocked beyond belief. I'm sorry, all right. I can't help it."

Dylan interrupted him from behind the camera. "It's what we had to do," he said.

Eric had one more thought, for the girl from prom night. "Susan, sorry. Under different circumstances it would've been a lot different. I want you to have that fly CD." Dylan got restless and snapped his fingers. Eric flashed an angry look. That shut him up. Eric had something profound to deliver. Dylan couldn't care less. Eric lost his big moment. "That's it," he said. "Sorry. Good-bye."

Dylan turned the camera to face himself. "Good-bye."

Eric and Dylan spent just five minutes firing outside. They killed two people and advanced into the school. For five minutes, they fended off deputies, shot Dave Sanders, and roamed the halls looking for targets. They began tossing pipe bombs over the railing, down into the commons, which appeared deserted. It was not. Several students hiding under tables made a run for it and fled out the cafeteria doors. They all made it out safely. Others stayed put.

Along the way, the boys passed the library windows, and ignored all the kids huddled there. Then they circled back. That room offered the highest concentration of fodder they had seen. They found fifty-six people inside. They killed ten, injured twelve. The remaining thirty-four were easy pickings. But Eric and Dylan got bored. They walked out seven and a half minutes later, at 11:36, seventeen minutes into the attack. Aside from themselves and the cops, they would not shoot another human again.

The boys wandered into the science wing. They walked past Science Room 3, where the Eagle Scouts were just getting started on Dave Sanders. They looked through the windowpanes in several classroom doors. Kids were inside most of them. At least two or three hundred kids remained in the school. The killers knew they were there. Many witnesses made eye contact. Eric and Dylan walked by. They chose empty classrooms to open fire.

They roamed aimlessly upstairs. To civilians, it seems odd that they stopped shooting and entered this "quiet period." It's actually pretty normal for a psychopath. They enjoy their exploits, but murder gets boring, too. Even serial killers lose interest for a few days. Eric was likely proud and inflated, but tired of it already. Dylan was less predictable, but probably resembled a bipolar experiencing a mixed episode: depressed and manic at once--indifferent to his actions; remorseless but not sadistic. He was ready to die, fused with Eric and following his lead.

Eric had a few thrills left to savor. Killing had turned tedious, but he was still up for an explosion. The biggest explosion of his life. He could still perform his primary feat: blow up the school and burn down the rubble.

He headed down the staircase into the commons at 11:44. Dylan followed closely behind. Eric stopped on the landing halfway down. He knelt and placed his rifle barrel on the railing to improve his accuracy. Backpacks were scattered everywhere, but Eric knew which duffel bag was his. He fired. The boys were easily within the blast area, and they were well aware of that fact. Twenty-five minutes into the massacre, Eric made his second attempt to initiate the main event, and his first attempt at suicide. He failed again.

Eric gave up. He walked directly to the bomb, with Dylan behind him. Dylan tried to fiddle with it. That failed, too. Kids were visible under some of the tables. The killers ignored them. Lots of drinks had been left on the tables, and the killers tipped back a few. "Today the world's going to come to an end," one of them said. "Today's the day we die."

The surveillance cameras picked up their movements in the commons. Their body language was vastly different than what witnesses in the library described. Their shoulders drooped, and they walked slowly. The excitement had drained out of them; the bravado was gone. Eric had also broken his nose. He was in severe pain.

They left the cafeteria after two and a half minutes. On the way out, Dylan tossed a Molotov cocktail at the big bombs--one last attempt to set them off. Another failure. Several kids felt the blast and ran.

The boys drifted about the school: upstairs and down again. They surveyed the damage in the commons. It was pathetic. The Molotov started a small fire that burned the duffel bag off one of the bombs and ignited some of the fuel strapped to it, but the propane tank was impervious. The fire set off the sprinkler system across the room. The boys had been going for an inferno; they caused a flood.

The killers were apparently out of ideas. They'd expected to be dead by now, but never planned how. The cops were supposed to take care of that. Eric predicted he'd be shot in the head. No one had obliged.

They had two essential choices: suicide or surrender. Eric would sooner die. He idolized Medea for going down in flames, but couldn't ignite his fire.

A cornered psychopath will often attempt "suicide by cop": an aggressive provocation to force the police to shoot. Eric and Dylan could have ended it dramatically by charging the perimeter. It would have been glorious. But it would take tremendous courage.

Eric craved self-determination. Dylan just wanted a way out. Alone, he might well have been talked down. He had been promising suicide for two years and never brought himself near it. He never had a partner to guide him out.

At noon, they returned to the library. Why end it there? Act III was about to commence. The car bombs were set to blow. Ambulances had massed around Dylan's BMW as planned. A triage unit was busy nearby. Limbs would fill the air, just like Eric's drawings. The library windows were set up like skyboxes. Eric and Dylan most likely chose the library, not just because of the carnage there already, but for a better view.

They found the room quite different than they'd left it twenty-four minutes before. Human decay begins rapidly. The first thing to assault them was probably smell. Blood is rich in iron, so large volumes emit a strong metallic smell. The average body contains five quarts. Several gallons had pooled on the carpet, coagulating into a reddish brown gelatin, with irregular black speckles. Aerosolized droplets dry quickly, so the spatters were black and crusty. Stray globs of brain matter would soon be solid as concrete. They would be scraped off with putty knives and the stubborn chunks melted down with steam-injection machines.

The killers had left the library in turmoil: shots, screams, explosions, and forty-two teens moaning, gasping, and praying. The commotion had ceased, replaced by the piercing fire alarm. The smoke cleared; a warm breeze floated through the blown-out windows. Twelve bodies shared the room with them. Two were breathing: Patrick Ireland and Lisa Kreutz had been fading in and out of consciousness, unable to move. Four staff hid in rooms farther back. Ten corpses had passed through pallor mortis, and livor mortis was setting in. The skin had gone white and purplish splotches were now appearing as the remaining blood settled.

The boys may have been oblivious. Mass murderers often shift into an altered state, dissociated and indifferent to the horror. Some barely notice, others take a clinical curiosity in variations like eyes either bulging or retracting, the whites clouding up or mottling with red clumps. If Eric or Dylan touched their victims, they would have found the bodies cooling noticeably, but still warm and pliable.

They walked on. Eric advanced toward a center window, among the heaviest carnage. He walked past the worst of it to get there. Dylan broke away and chose a spot closer to the entrance, half a dozen window panels down. If he took a direct route, he followed one of the cleanest pathways left.