"No," said Ochoa, "but we found something you'd call an Odd Sock. Made us wonder if it might point to a new victim."

"These are copies from Douglas Sandmann's accounts receivable." Raley held up a file. "We found a pattern of him performing bedbug checks in buildings, but getting paid by a third party who has no connection with the buildings Doug inspected."

Ochoa picked up. "So we asked his wife about it, and she says, 'Oh, yeah, Doug made some money on the side from that guy because he could get into buildings and apartments pretending to do his inspections.' "

"But he was really snooping undercover for the guy who paid him. You know, the third party," said Detective Raley.

"And here's what set off the alarm bells in our heads," continued Ochoa. "Know that little hand snipped from the oil painting the serial killer left us? This third party guy is in the art business."

"I a.s.sume you got a name," said Heat. Raley opened the file. Nikki reeled when she saw who it was.

By the time Heat, Rook, and the other detectives rolled down to the marina on the Hudson at West 79th Street, Parks Enforcement had already found Joe Flynn's body. It bobbed three feet under the surface of the river, tethered between the marina dock and the fifty-foot ketch he had lived on. They didn't need a coroner to know he was beyond CPR; Flynn's eyes bulged in their sockets, peering skyward through the murky water from a swollen face. His body had bloated with gas, and his skin had changed color to a pallid shade of green.

Distant thunder mixed with the pair of diesel 60s from the harbor unit response boat that slowed up to kill its wake on the other side of the Boat Basin's wave wall. The smooth water in the protected marina broke with the first drops of the approaching storm. Heat got down on one knee. Through the dimpled river surface she could see the wooden handle of a small knife, something a painter would use-perhaps a palette knife-protruding from Joe Flynn's throat. She also noted that his body wore no shoes. He had a sock of a different color on each foot: one light, one dark.

"Boat's clear," said Detective Feller, climbing from belowdecks to the c.o.c.kpit. "Detective Heat?" The slight waver in Randall's voice made her and all the others turn his way.

Nikki put on her crime scene gloves and climbed aboard.

Wordlessly, Randall Feller stood aside from the hatch to allow her to pa.s.s. To preserve fingerprints and DNA, Heat avoided touching the polished bra.s.s rail as she descended the teak steps leading below to the main cabin, an opulently appointed s.p.a.ce which functioned as the galley and den. Nikki heard footfalls behind her and made room for the other detectives and Rook to come below.

The cabin had sufficient height for them all to stand, and there-right before them, at eye level-an eight-by-ten head shot of Joe Flynn, captured from the Quantum Recovery Web site, dangled from the ceiling. It hung from a row of equal, six-inch lengths of colored string: red, yellow, purple, and green. Colors of the rainbow.

Finally, after a few silent moments of watching the latest victim's photo wave slightly with the rocking of the boat, Heat said, "Do you all see the pattern?"

"Hard to miss," said Ochoa. "Each color of string corresponds to the string found with one of the victims."

"And there's a new string," said Feller, speaking for the first time with a voice that sounded thick in his throat. They all followed him behind the photo. Taped to its back, a new color-orange-was strung like a clothesline to the forward cabin, where its end disappeared around the bulkhead door.

Together, Roach moved to the forward compartment to see if it linked to some clue to the killer's next target. They were only gone a moment.

Both detectives returned looking ashen.

NINE.

"I'm ordering protection for you, Heat. Trust me, this a.s.swipe isn't going to get near you." The springs of the executive chair creaked under Captain Irons as he rocked back and crossed his arms in front of his belly. She tried to ignore the fact that his hands could barely meet and he had to be satisfied lacing his fingers.

"I certainly appreciate the support, Cap, but-"

"No buts. I can't have the NYPD's cover girl killed on my watch." So nice to know, she thought, that his concern for her safety was really just the flag Wally wrapped around his worry that her murder could be a career hindrance. Nikki would push back on the round-the-clock detail he had proposed, and win. But even she had to admit how deeply unsettling it had felt to follow the orange string into the forward cabin of that boat and see it link from the latest victim to her own picture. The captain's cover girl ref wasn't lost on her, either. The serial killer's photo of choice was a printout of her cover shot from Rook's FirstPress.com article.

"With all due respect, sir, risks like this come with the job. I'm armed, trained, and this guy's worst nightmare. Plus with two big cases in my lap, there's no way I can be hamstrung in my investigations by tripping over a detail of unis or grade-threes who can't keep up." Or worse, Sharon Hinesburg, she thought but had the restraint not to mention.

"Not making me feel any better here, Heat. You've not only got two cases going, but two death threats. I'd say wake up and smell the coffee, but there might be cyanide in it."

"Hilarious, sir."

"You know d.a.m.n well what I mean."

Since Heat couldn't convince her precinct commander with logic or bravado, she played her ace: fear. "Your call, Captain. Which is why it'll be too bad when the media gets word that you did something to slow me down and impede progress on these cases."

"Who would say something like that?"

She shrugged. "Things get out. You know that."

He paused and signaled his surrender by telling her to watch her a.s.s and to call in backup even if she heard an alley cat screech. Heat left his office feeling relieved. Good thing she didn't tell Irons about the return call she'd just gotten from her NCAVC friend in Quantico. The FBI a.n.a.lyst told Nikki she had gotten two hits when she added the terms "law enforcement outreach" and "electronic voice alteration" to her database search for multiple unsolved homicides. In each case a suspect claiming to be a serial killer had made anonymous contacts with detectives, in Bridgeport, Connecticut, in 2002 and Providence, Rhode Island, in 2007.

Both detectives were dead.

Heat called Helen Miksit to tell her she'd be a half hour late for the appointment she'd made with Algernon Barrett that day. Predictably, the Bulldog bristled, accusing Nikki of playing a mind game to throw her client off balance. "Counselor, if I wanted to play a mind game, I wouldn't have made this courtesy call. I would have left you sitting there wondering where the h.e.l.l I was."

She needed the extra time to contact the homicide squads in Bridgeport and Providence. Heat could have delegated these checks to her own crew, but that might have raised alarms, and next thing, she'd have been shackled to a protection detail. The detectives in both out-of-state departments recalled the cases clearly and didn't need to research old notes; cop killings never go cold.

The cases in both cities remained unsolved. Referring to the Murder Boards across the bull pen, Detective Heat shared bullet points from her own serial killer, including victims and MOs. None matched hers: no colored strings; no props; no apparent connections between victims. The only similarity was the killer's outreach to the case's lead investigator by phone with the altered voice. When she asked how each detective died, she got one additional similarity. Each one had been shot unexpectedly after being lured into an ambush set up by the killer.

The glorified closet Rook and Detective Raley had commandeered to follow the consumer trail of Tyler Wynn had outgrown itself with the addition of Malcolm and Reynolds to the detail, so the operation moved to more s.p.a.cious digs in a far corner of the bull pen. The three detectives chattered simultaneously on calls to retail distributors around the country, acc.u.mulating tracking data from the RFID chips in the packaging of Wynn's favorite brands. They relayed their findings to Rook, who, between his own calls, pushed colored pins into a tristate map to mark the delivery zones for everything from outerwear to whiskey to sungla.s.ses to artisa.n.a.l sausages.

"The thing is," said Rook to Nikki as she came over to him, "that we don't know which-if any of these-are products going to Wynn. But the idea is that if enough of these items intersect with his consumer habits, we'll be able to narrow the list when we see a discrete pattern."

"Right, so if only five people are buying, say... Barbour coats, Whistlepig rye, and D'Artagnan rabbit-and-ginger sausage, you've, at least, tightened the likely prospects and we can go knocking on doors." She looked at the colored pins on his map and added, "Not seeing much of an overlap yet."

"It's slow going."

"But it feels promising. Keep at it. I'm heading over to interview Joe Flynn's a.s.sistant and then on to Algernon Barrett."

"Really."

She didn't like the judgment. "Rook, you know how hard I've been working to brace him."

"I do. It's just... first the Tyler WynnSalena crew wants you dead. Now the serial killer? Is it really wise for you to be gallivanting around with two killers hunting you?"

If life wasn't s.h.i.tty enough, Nikki felt him planting the fear seed, and if that took root, she knew she might as well be dead. So she pushed back. "Rook, I refuse to live my life in paranoia. And the only sure way for me to stop them is to get out there and stop them."

"Oh, splendid logic," he said with some bite. "Maybe with any luck they'll both come after you at the same time and you'll be able to duck so they'll kill each other."

Heat interrupted his sarcastic laugh, s.n.a.t.c.hing him by the shirt and drawing him out of earshot of the others. "I will say this once. This is what I do. I mult.i.task. I spin plates. I live in danger. I have to. Why? I'm throwing John Lennon back in your face, Rook. Murders happen while I am making other plans. But I see my plans through. And yes, that includes following up on persons of interest like Algernon Barrett."

On her drive to midtown, Heat calmed herself to the rhythm of her wiper blades in the rain. Rook had hit a hot b.u.t.ton but apologized, saying he was freaked about that orange string ending on her picture. Nikki cut him slack for that. In fact, she found herself extra vigilant, scanning windows and rooftops outside the precinct on the walk to her car. Even the thunder cracks made her jumpy. By the time she ascended the elevator to Quantum Recovery's floor, she decided snapping at Rook called for some smoothing over later.

Joe Flynn's a.s.sistant sat with the lights off in her dead boss's office. Grim midday sun, filtered through rain clouds, erased the colors from the large-format paintings on his walls. The young woman's eyes were puffy and cried-out. Nikki approached the interview gently, empathically. But her questions about the private investigator's recent activities, behavior, new clients, etc., brought no more light into that room. The PI's schedule had been to-pattern; his att.i.tude remained good-humored; he had no conflicts, disputes, or threats in his life. The only thing out of the ordinary was that Flynn had misplaced his iPad, prized because it was a beta version, a gift from Apple after he recovered a lost prototype. It still hadn't turned up. The a.s.sistant said her last communication with Joe Flynn had been when he left the office a few days before. She didn't find it odd that he didn't check in, because he did that sometimes when he was on a case. He called it the romance of chasing international art thieves, and had always surfaced, eventually, with jet lag and cool stories. "Did he say where he was going?"

"Not specifically," said the a.s.sistant. "Just to meet someone with information about a stolen painting Joe wanted to recover."

"The Cezanne?" asked Heat. The a.s.sistant raised her head up in surprise. Nikki took out her photocopy of Boy in a Red Waistcoat.

"How'd you know?"

Randall Feller arrived, and Nikki put him on checking phone logs, e-mail, Internet history, and bank records. He suggested his routine checks could wait, and that he should ride shotgun with Heat to her meeting in the Bronx. The detective didn't take his no easily.

Heat did a little bit of self-talk crossing the Harlem River. Her encounter with Algernon Barrett about a month ago had been contentious and, essentially, nonproductive. Back then, Barrett was a person of interest in her mother's murder hiding behind his lawyer's pantsuit, so Nikki bad-copped him into losing his temper to see what shook loose. Nothing did, so this time-especially since she didn't regard him as a potential murder suspect-she decided to play nice, to be the kinder, gentler cop, and see if that got any more out of him.

The Jamaican had risen from poverty, coming to New York in the early 1990s as an immigrant running illegal horse bets from his sidewalk food cart. His live-in girlfriend, a business major at Fordham, drew up a marketing plan for a company to sell Algernon's Caribbean spice rub recipes, and within two years, Do the Jerk broke the million-dollar profit ceiling and kept climbing. When Heat pressed the b.u.t.ton to announce herself at the driveway on an industrial block of 132nd Street, the iron gates that rolled aside led to the headquarters of a food empire built on the lore of a New American's success story.

She found the pair as she had left them a month ago. Except for the clothing, Algernon Barrett and his lawyer might have never departed his office. The jerk spice magnate in the track suit sat behind his desk with a turquoise Yankees cap floating atop his shoulder-length dreadlocks. At a side chair, Helen Miksit acknowledged Heat without standing. Nikki began her charm offensive by leading with a smile and energetic handshakes for both.

"Thank you for making the time. You must be busy. I noticed a lot of people lined up in your parking lot. Are you holding a job fair?"

"You don't have to answer any of that," said the Bulldog. "Detective Heat, you said you had a few questions about helping you ID suspects. Let's stick to the agenda."

Algernon slid off his Kate Spade Vita sungla.s.ses. "I don't mind. Lets her know I'm not some punk to f.u.c.k with, right?" He turned to Nikki. "I'm expanding. The food truck thing is so yesterday, mon. Pop-up stores, that's the thing. I just secured permits to set up surprise locations at all the prime New York spots. No more playing Where's the Jerk? on social media. This week people are going to be seeing my Do the Jerk stores springing up at Grand Central, Empire State Building, Columbus Circle, Union Square, outside all the stadiums." He slipped the Vitas back on. "You want a job?"

"You never know. But congratulations, Mr. Barrett. I'll have to come by."

He stood and opened the desk drawer. "I'll get you a free coupon." He found one and handed it to her, an oversized fake dollar with his picture in the statesman spot. Helen Miksit then suggested the detective move along to business.

"First of all, Mr. Barrett, you are not under any suspicion. I am merely seeking your help because my mother tutored your daughter in piano..."

"Ah, sweet lady, that Cynthia."

"... Thank you. Anyway, I wanted you to think back to that time. May I ask if you ever saw any of these people?" She came to the side of the desk and set out twin head shots of Tyler Wynn, one circa 1999, the other present-day. He studied them at length then shook no. When she placed the photo of Salena Kaye on his blotter, Nikki caught a reaction. "What, Mr. Barrett? You recognize her?"

"No, but I'd sure like to. I'd have a fine time with that." He chuckled salaciously.

"Trust me, you wouldn't." She moved on to her last picture: the surveillance shot of Dr. Ari Weiss and Francois Sisson, Wynn's Paris doctor, taken as both men talked in the front seat of a parked car.

"I'm sorry," said the Jamaican. "Don't know them, either."

"So we're done," said Miksit, getting to her feet. "And by done, we're done-done, right? My client will be left in peace?"

"Absolutely. But just one more question." Nikki sat. The lawyer sat, too, but not without checking her watch. "Mr. Barrett, would you try to think back? Do you ever recall seeing my mother with anyone, even if it was before or after those piano lessons?"

He tilted his head toward the acoustical tile to ponder, twirling the end of a dread. He began to shake his head but then said, "You know, one time I remember. I remember because, hoo, I got p.i.s.sed off." Heat gently opened her spiral pad. "I got p.i.s.sed off because my little Aiesha's lesson got interrupted. See, that day we had our tutoring session in Cynthia's place in Gramercy Park because I had business in Manhattan. Right in the middle of the lesson, buzz-buzz, someone's at her door, and Teacher Heat says, 'pardon me,' and goes into the hallway, leaving my girl to sit there while she argues with someone."

"Did you hear what they were arguing about?" Nikki leaned forward in her chair, full of new antic.i.p.ation.

Miksit stuck her nose in. "Detective, it was over ten years ago, how would he remember what they were arguing about?"

"Money," said Algernon Barrett. "When somebody talks big money, it's not something you forget."

"What money? How big?" asked Heat. "Can you remember?"

"Not only can I remember how much, I remember what your mom said." Nikki paused her note taking and glued her eyes to him. "Teacher Heat, she say, 'Two hundred thousand dollars is nothing to you people, so get off my back.' "

Barrett had just named the exact amount of FBI seed money Agent Callan gave her mother to bribe her informant. "Did you hear any more of the argument?"

He thought about that and said, "That's all that sticks."

"By any chance, did you happen to see who my mother argued with?"

"Lady, you kidding? Anybody says two hundred long is no biggie to somebody, I'm gonna see who it is." He curled the fingers of one hand to his palm and looked at Nikki through the tunnel he'd made. "I peeped the peep hole in that door." He paused. "Looked like a cop."

Heat had expected that. Just for drill, she asked, "Can you describe him?"

"Him? Wasn't a him, it was a her."

"And she looked like a cop?" Nikki drew a line through Callan's name. "Can you describe her?"

He thought again. "Sorry... It's just been too long." He laughed. "And too many spliffs."

His attorney quickly added, "That is a figure of speech, not an admission of guilt."

That evening, Rook's only response to Nikki's conversation with Algernon Barrett, including his plans for jerk chicken pop-up stores, was to say he was starved and insist they dine like human beings. "We can still be dedicated, nay, obsessed investigators and enjoy at least one meal that isn't delivered in a greasy bag with a menu number instead of a food name."

"I don't know," said Heat, "I really enjoy my forty-sixes, hold the elevens."

"They all start tasting like number two to me."

"Appetizing."

"I'll make it up to you." And he did. Just stepping into Bar Boulud, Daniel Boulud's French bistro, across from Lincoln Center, Nikki's guilt about taking some downtime melted away. "Besides," as Rook pointed out, "we can still talk shop, if we keep our voices down." They scored a back table at the far end of the charcuterie, and as she sipped her Sidecar and he his Prohibition Manhattan, Rook observed, "Here's how immersed I am. I look at all the saucissons and fromages behind that bar, and all I can see are Tyler Wynn's buying habits and how far we have yet to go."

"Nice to get away from the office," she said, rubbing her toe against his leg under the table.

"Actually, it is." He set down his gla.s.s and lowered his brow. "I miss the 'us' part of doing this."

"We're working together."

"Yes and no. It feels more to me like parallel play instead of teamwork. You're doing your thing, I'm off doing mine. I miss you. I miss our connection. I want it to be like old times. And by that, I mean a month ago."

"Likewise. But welcome to police work. This is what you do when it all piles on-and why I flared at you earlier today. I'm sorry. However, the beach and the Janet Evanovich are still out there."

"And the s.e.x."

"Count on that." Both their cell phones were in front of them. She swept them aside with her forearm and patted the tabletop. "Right here. Wanna?"

"Detective, please," he said in mock reproach. "You're a marked woman. Behave."

They ordered the grilled day boat scallops and a Colorado lamb cavatelli. While they shared plates, she recapped her visit to Quantum Recovery. After her rundown, he said, "You know what I can't shake about this Joe Flynn murder?"

"Uh-oh. I know that tone. Do I hear the revving of the conspiracy engine?"