"DON'T TELL ME WHAT TO DO!" William screamed. "YOU'RE NOT MY MOMMY!"

"I know I'm not your mommy, but I work for your mommy."

"No, you don't-you work for ANNA," William spat.

Back at the blanket, Mara recounted what the Dartmouth-undergrad-look-alike had said to her. "It was like I said 'au pair' but he heard 'hooker'!"

Eliza rolled her eyes. She could have warned her about using the "a" word to describe herself. "Most of the young investment banker types around here think au pairs are easy summer lays with little or no responsibility. Stay away from them; they rent tract homes in Westhampton and are totally not worth your while," Eliza advised.

Madison removed a Ziploc full of gummi bears from her pocket. She nudged her brother. "The other au pairs were a lot nicer."

"Wait. What other au pairs?" Mara demanded.

"Camille, Tara, and Astrid. They were taking care of us because Nanny went back to England this summer," Zoe piped up.

"What happened to them?" Eliza wanted to know.

"They were fired," William said gleefully. "It was funny." He hugged his knees, remembering how the Porsche Cayenne careened through the streets of East Hampton and screeched to a halt at the Jitney stop and how his stepmother used bad, bad words as she threw their suitcases out of the window.

"Fired?" Mara asked, a chill in her heart. The possibility had never occurred to her. That would totally ruin her plans to earn enough money for her college tuition.

Fired? Eliza thought. Now, that would definitely complicate matters. She was supposed to spend the whole summer here-God help them if they tried to ship her back to Buffalo.

Jacqui didn't much care about being fired. As long as they did it after she found Luca.

"I miss them," Zoe said. "Tara was supposed to braid my hair today."

But before they could ask them any more questions about this mystery, a particularly loud firecracker exploded and Cody started to bawl again.

"Oh my God, can you hold him? What should we do?" Eliza said, thrusting the toddler into Mara's arms.

"Shh . . . shh . . .," Mara said, rocking him on her lap and trying to hum a lullaby.

"Thees one says she's a little hungry," Jacqui said, pointing to Madison. "Maybe we give her something?" she asked when Mara had her back turned.

"What's in the basket?" Eliza asked.

"Pringles."

"Yeah, fine." Eliza shrugged.

Mara looked up. "Hey, where'd William go? William! Stay here! On the blanket! Don't move!" Mara said in her best sophomore class secretary voice. "Zoe, come on, honey, look at all the colors, aren't they nice?"

"Cody, it's okay, baby, it's only fireworks. I know, they're loud, but it's okay," she soothed.

A few minutes later the kids were crowded around Mara, who put an arm around all of them. "Look at that! The Stars and Stripes! Have you ever seen anything so beautiful?" Mara asked the little girls, who were sitting raptly looking at the night sky. The boys were passed out on the blanket, William utterly spent from chasing dragonflies and Cody sleeping in his stroller with his thumb in his mouth.

Eliza looked at her cell phone. Uh-oh. Almost eleven. Time to motor.

"Hey, you know what, I've got to run. I'm meeting some friends . . .," Eliza said, brushing grass stains off her knees and starting to walk away.

"Excuse me?" Mara asked.

"Where are you going?" Jacqui asked.

"Party. Wanna come?" Eliza said.

"Si." Jacqui nodded, standing up.

"Yeah, after all, you've got things under control here, right, Mary?" Eliza asked. But before Mara could answer, Eliza and Jacqui were running down the hill as fast as their stilettos would take them.

resort is the hottest party in the hamptons. at least until next week..

ELIZA TOOK A DEEP BREATH AS SHE SCANNED THE MOB scene outside Resort. Five hundred people were elbowing each other to get closer to the velvet-roped entrance, and there was a backup of twenty stretch limos parked on the driveway, waiting to discharge their famous (or merely showy) passengers. Skinny, toothpick-sized women with significant cleavage, lathered in layers of foundation, blush, and hair spray, wearing brightly colored tank tops and formfitting knee-length skirts, picked their way across the gravel in spindly sandals. Their dates, slick older men with equally artificial tans, jangled enormous gold bracelets on their hairy wrists.

Two spotlights directed up in the air lit the entire scene like a movie set. Several overwhelmed publicists tried to control the crowd while burly, three-hundred-pound bouncers glared at the overeager revelers.

Eliza fought her way to the front armed with the magic words: I'm on the list!

"Eliza Thompson!" she screamed at a beleaguered girl in a headset.

After rifling through her pages the door girl snapped, "You're not on the list. You'll have to wait in line."

"Under Kit Ashleigh?!"

"You should have said that you were on Kit's list in the first place," she said sullenly. "What did you say your name was again?"

"ELIZA THOMPSON!"

"Oh, there you are." The girl nodded at the gorilla in the three-piece suit. He lifted the rope reluctantly. Eliza tugged at Jacqui's arm, and the two were swept inside the nightclub.

They found themselves in the middle of a chaotic scene, and Jacqui felt the familiar rush she felt whenever she was somewhere new, uncharted, and maybe even slightly dangerous. She licked her lips in anticipation. She was certain Luca was here somewhere. She could feel it.

"Hold up!" Eliza said, grabbing Jacqui's arm. "I see my friends over there."

Kit was sitting in the middle of the biggest banquette in the middle of the packed VIP room. His face lit up when he spotted Eliza. "Liza!"

"Kitty cat!" she shrieked, giving him a two-cheek air kiss as if they hadn't just seen each other a few hours before.

"Who's your friend?" Kit asked, wagging his eyebrows at Jacqui.

"Jacqui Velasco. She's, uh, an exchange student . . . living with my uncle's family," Eliza said before Jacqui could open her mouth. She gave Jacqui a mute plea to play along.

"Si." Jacqui shrugged. What was that all about?

"Cool," Kit said. "What are you studying?"

"Design," Jacqui said.

"English," Eliza replied.

They looked at each other. Eliza laughed nervously. "English design, right, Jac?"

"Whatever," Jacqui conceded. She was too busy scanning the room for a sign of her beloved to deal with Eliza right now. But she was polite enough to smile at Kit, who beamed at her.

"About time you got here!" Kit's girlfriend, Taylor, said to Eliza as she squeezed herself between her man and the hot South American girl.

"You're back!" Lindsay, another friend, crowed, coming to join them.

"My girls!" Eliza said, triumphant.

So many people were coming up to hug and kiss her she felt like homecoming queen. Except that she'd never be caught dead at something as lame as a high school dance. This was homecoming Eliza style: frozen margaritas, flowing bottles of Cliquot, hot guys, good shoes, even better cars parked outside.

"Sweetie, you look fantastic!" Taylor said in an admiring and slightly jealous tone.

"You must be starving yourself!" said Lindsay, the master of the left-handed compliment.

"Is Charlie here?" Eliza asked, a little too eagerly.

"Not yet. Why?" Lindsay asked, narrowing her eyes.

"Nothing. I just thought it would be nice to see him, for old times' sake." Eliza shrugged.

Lindsay and Taylor exchanged a knowing look.

"Well, look who's here," purred a voice from behind the champagne bucket. A sloe-eyed blonde with a vixenish pout appraised them coolly. She was wearing a pink beret, aviator sunglasses, and a tight baby T-shirt that showed off a completely flat midriff.

"Sugar!" Eliza said, bending down to say hello.

"Careful-I just had it blow-dried," Sugar Perry said, turning away before Eliza could get any closer.

"How are you?" Eliza asked, sliding into the seat next to her.

Sugar was the most popular girl at Eliza's old prep school. At least, she was now that Eliza had left.

"I'm all right," Sugar drawled, taking a cigarette from Eliza's pack and tapping it on her hand. "I'm so over this scene."

"I know, it's so boring. The same every year." Eliza knew this was the right thing to say in the Hamptons, even though the truth was, she was thrilled to be back.

"You're so lucky your parents sent you to boarding school." Sugar sighed. "If only I could get away from mine."

"It's never going to happen," added a similarly hoarse voice. Eliza looked up to see Sugar's identical twin, Poppy, looming over them.

"Eliza, you're back," Poppy said flatly. She had the same long platinum Donatella-Versace-like locks as her sister, the same seductive languor, but where Sugar had the makings of a porn star in a debutante body, Poppy, who was taller and two minutes younger, projected a more innocent air. Sugar was sexy; Poppy was just cute.

Finding the banquette fully crowded, Poppy parked herself on Eliza's lap without a second thought. Eliza didn't have the nerve to complain. She was too excited not to have to answer any difficult questions. Taylor and Lindsay receded to the background, pretending not to be bothered that Eliza had replaced them for the twins without a second thought.

Meanwhile, after downing two quick flutes of champagne and making chitchat with some of Eliza's friends, Jacqui scanned the room again. These people were nice enough, and yes, she could tell they were rich, but after meeting Luca, Jacqui had started caring less about those things. Before him she probably would have made her way straight over to the handsome Almost Forty who was staring at her from across the room-Jacqui knew the benefits of seeing an older man (hello, expense account)-but Luca had changed everything. For once she had found a guy who really liked her for who she was, not what she looked like.

Jacqui looked around, trying to look through the older man still staring her down. I can see your wedding ring, she thought. And then a flash of familiar stripes made her sit up a little straighter. Was it? No way . . . there was no way. But it was worth a shot. She stood up, pulling her underwear-completely-optional-low-rider jeans up with her, and she walked off to follow the lanky guy wearing a very familiar-looking rugby shirt.

back at the beach, mara got blown off so eliza could blow out her hair.

MARA COULDN'T BELIEVE THEY PULLED THIS ON THE first night. She packed up the picnic basket, trying to keep an eye on the one-two-three-four (thank God they were all there!) kids. "All right, everybody, follow me."

"Don't want to go! Want to stay play ou'side!" Zoe whined.

"Can we go over there? There's ice cream," Madison said, pulling at Mara's hand.

"Why you want ice cream for? Porky Pig Porky Pig!" William jeered. He started snorting and making noises with his armpit.

"William!"

"William!"

"WHAT???"

"STOP MAKING THAT . . ." Mara clapped. "Arrrghh!"

William, who was clearly enjoying torturing his sister, cackled. Madison was nearly in tears.

"Hey, buddy, that's not nice."

Mara looked up to see Ryan Perry standing next to her, holding a death's-head skateboard in one hand. He wore a faded Groton sweatshirt over his frayed shorts. He smiled at Mara, then put a hand on William's head and turned the kid around. "Apologize to Maddy."

"Erm sorry." William sniffled.

Madison stuck a chocolate-covered tongue out at her brother.

"I saw Eliza and Jacqui back at the house. I figured you might need a hand," he explained.

"Oh-that's so nice. Really, though, it's all good," she said, just as William wrestled Madison to the ground and the two of them began rolling down the hill toward the ocean.

"No-no-no-come back!" Mara cried.

"Don't worry, they won't get far," Ryan promised as he picked up the picnic basket. "Hey, cool, you brought the Scrabble," he said when he spied the board game among the Tupperware.