Seventeen: Dance Like No One’s Watching.

"There's a spot!" Spencer bellowed, pointing to an empty space on the side of Walnut Street in downtown Philadelphia.

Zach nodded, wrenched the wheel of his Mercedes to the right, and pulled in neatly behind a dented Ford Explorer. "Am I a genius parallel parker to what?"

"The best," Spencer said.

She peeked at Zach out of the corner of her eye. Tonight, he was wearing fitted dark-denim jeans, a striped Paul Smith button-down, shiny wingtips, and a pair of aviator sunglasses on his head. He'd splashed himself with a spicy, woodsy cologne, and he'd combed his hair off his head so she could see every angle of his fine-boned face. Each moment Spencer spent with Zach, he got cuter and cuter.

And tonight, she had him all to herself.

It was Thursday, a school night, but Zach was sneaking out to Club Shampoo in Philly to see his favorite DJ spin and asked Spencer to come along. When he'd picked her up earlier this evening, she was thrilled to see Amelia wasn't glaring at her from the front seat. "She had flute practice," Zach said as soon as Spencer opened the door, as if reading her mind. "We're free!"

A pulsing bass assaulted Spencer's ears as soon as she stepped out of the car. She straightened her clingy black dress, rotated her ankles in the ultra-high Elizabeth and James heels she'd stolen from Melissa's closet ages ago, and followed Zach toward the group of people waiting behind velvet ropes at the door. As she crossed the slick-with-rain city street to join the line, her cell phone buzzed. She pulled it out of her sequined clutch and stared at the screen.

Aria: I just heard from A. Have you?

The words sent a knife through Spencer's chest. Should she have told the others about her A note?

I'm not paying attention to A, Spencer typed back. Neither should you.

Aria replied immediately. What if A knows?

A car blared its horn, nearly sideswiping Spencer. She jumped away, still staring at her phone. Should she reply? Should she worry? Or was that exactly what A wanted?

"Spencer?"

When she looked up, Zach was standing at the front of the line. The bouncer had unclipped the rope and opened the door for him.

"Coming!" Spencer slipped the phone back into her purse. She couldn't deal with A right now.

The music thrummed in Spencer's wars as she ducked into the dark, industrial space. Vague outlines of bodies stood at the bar and gyrated on the dance floor, backlit by neon flashing lights and round, swinging bulbs. Zach was right about Thursday being the night to go out—Shampoo was packed, and the air was humid and sweaty. Four bartenders worked efficiently, pouring drinks so quickly they barely even looked down at what they were doing. Beautiful girls in barely there dresses turned to smile at Zach, but Zach didn't even notice them. His eyes were squarely on Spencer. Swoon.

"Two mojitos," Zach told a bartender, using the proper Spanish intonation. Their drinks arrived quickly, and they found a table in the corner. It was almost too loud to speak, so for a while Spencer and Zach just sat and watched the crowd. More girls eyed Zach as they swept by, but Zach acted like they didn't exist. Spencer wondered if everyone assumed the two of them were boyfriend and girlfriend. Maybe they would be after tonight.

Finally, Zach leaned so close to Spencer that his lips nearly touched her forehead. "Thanks for coming with me tonight. I needed to blow off some steam—my dad's been relentless lately."

Spencer sipped her mojito, which tasted kits like summer. "He's that bad?"

One of Zach's shoulders rose. Lights flashed across his face. "He wants us to be little clones of him, doing exactly what he wants at all times. The thing is, I'll never be like him. For so many reasons." This last part he seemed to mutter more to himself than to her.

"Your dad does seem intense." Spencer agreed, thinking about how Mr. Pennythistle grilled her about her grades at the restaurant.

"Intense isn't even the half of it. If I don't go to Harvard like he wants, I'll probably be disowned. I'm supposed to talk to some guy named Douglas when we go to New York this weekend. He's on the Harvard admissions board. But I'm thinking about bailing."

Spencer nodded, catching his reference to traveling to New York for the long holiday weekend. She and her mom were going to New York City, too—Mrs. Hastings and Mr. Pennythistle were attending a gala hosted by one of Mr. Pennythistle's real estate friends. The idea of twenty-four hours in New York with Zach sounded delicious.

"What about your sister?" Spencer moved out of the way as a raucous bachelorette party, complete with penis balloons and a girl in a long, trailing veil, tramped through the narrow space. "Does she have to go to Harvard, too?"

Zach made a face. "My dad's a lot easier on her. She's quiet, demure, always proper—at least around him—so he adores her. But me—everything I do is wrong."

Spencer stared into her glass. She could certainly relate. "That's the way things used to be with my family, too."

"Yeah? How?"

Spencer shrugged. "Whatever I did wasn't good enough. I'd get cast in the school play, but Melissa would be cast as an extra in a movie being shot nearby. I'd get an A on a test, Melissa would get a perfect score on her SATs."

Zach squinted at her in the dim light. "You guys seemed okay at dinner."

"We're better now—although it'll probably never be perfect. We're too different. And it took going through the Alison DiLaurentis thing together to really change things. Alison almost killed Melissa, too."

It was strange to utter those words so baldly and effortlessly in a public place. The admission seemed to startle Zach, too, because he took a big sip of his drink and stared at her long and hard. "I don't mean to pry about that Alison stuff, but are you okay?"

The door to the club opened, bringing in a whoosh of freezing air. Goose bumps rose on Spencer's bare arms. But it wasn't entirely from the cold. Aria's texts drifted into her mind.

"I'm okay," she said quietly. But as she looked around the club, a spear of despair ripped through her. It was at a place just like this where the girl Spencer thought was Courtney said she was actually Spencer's long-lost best friend. Then, Real Ali admitted that she'd known for a long time that she and Spencer were actually half sisters, but she'd never known how to tell Spencer back when they were friends.

Ali had made so many promises. We'll start fresh. I'll be the sister you always wanted. Of course Spencer had fallen for it, she'd longed for a sister who truly cared about her ever since she could remember. Someone with whom she had something in common, someone with whom she'd share secrets and have fun. With Ali last year, she felt like she'd hit the jackpot—until Real Ali revealed her true identity and tried to kill her, that is.

Letting go of the dream had been hard; its dark cloud had followed her everywhere. It stung, even when she saw girls who were obviously sisters giggling together at the bar or renting a two-person kayak. After she'd shared a drink with Tabitha in the bathroom, she returned to their table. Her friends had scattered—Aria was arguing with Noel at the bar, Hanna stood by the telescope on the other side of the restaurant, and Emily was nowhere to be seen. After a while, someone tapped her arm, and she turned. It was Tabitha again.

"Sorry to bug you, but I have to ask." Tabitha perched on the edge of the table. "Don't you think we look similar?"

Spencer stared at her, a nervous swoop running through her body. "I don't think so."

"Well, I do." Tabitha grinned. "I think we look just like long-lost sisters."

Spencer shot to her feet so fast that the chair underneath her tipped over. Tabitha remained where she was, a Cheshire cat grin on her face. Why would she say that? Could she know? The story of Mrs. DiLaurentis's scandalous love affair with Mr. Hastings was something that hadn't been released to the public. Spencer wasn't even sure if the police knew about it.

The rattling sound of a martini shaker startled her from the memory. She glanced around Shampoo. "Jesus," she whispered to herself. Hadn't she vowed not to think about Jamaica tonight?

The DJ put on a fast, electronic song, and Spencer stood and grabbed Zach's hand. "Let's dance."

Zach raised his eyebrows, looking amused. "Yes, ma'am."

The dance floor was packed with sweaty bodies, but Spencer didn't care. She led Zach to the middle of the room and started to sway. Zach gyrated, too, shutting his eyes and feeling the music with his body. Unlike most guys, who shuffled back and forth like Frankenstein's monster, Zach fancied like a pro. He didn't freak when other guys bumped him, either, but just shrugged and went with it. He opened his clear, blue eyes, met Spencer's longing stare, and winked.

Spencer threw her head back and laughed. He was the sexiest guy she'd ever met. The voltage between them was cranked up as high as it could go.

She leaned into his ear. "This is awesome."

"I know," Zach answered. "You're a great dancer."

"So are you."

The beat slowed down, and Zach and Spencer moved closer and closer to one another until their hips touched. Spencer's heart clanged in her chest like the clapper in a bell. When she opened her eyes, all she could see were Zach's beautiful lips. He opened his eyes and gazed at her, too. She moved an inch closer. Zach edged in, too. Here goes…

Taking a deep breath, Spencer grabbed the back of his neck and planted her lips on Zach's. He smelled like a spicy face cream and tasted like sugar and lime. His lips were stiff for a moment, but then they opened and let her in. Spencer's stomach did somersaults. Electricity snapped off her skin. She raked her hands through Zach's stout hair, wishing they could fall into bed.

But then Zach pulled away. The strobe light danced across his face. He looked confused. Upset. Spencer took a few steps back, too, heat immediately rising to her cheeks. It felt like everyone was looking at her, laughing at her.

Zach grabbed Spencer's arm and pulled her into a sitting area just off the dance floor. He settled down on the plushy velvet couch under billowing canopies. It was the sort of place couples tumbled into to make out, but suddenly the moment felt charged in all the wrong ways.

"I think you've misunderstood," Zach said. "Maybe I've misled you."

"It's fine," Spencer snapped, staring pointedly at the glowing disco ball in the center of the dance floor. "So what is it? Do you have a girlfriend or something? Are you freaked out that our parents are dating?"

"It's not any of that." Zach shut his eyes. "Actually, Spencer…I think I'm gay."

Spencer's jaw dropped. She stared at Zach's thick eyebrows and strong shoulders, not believing it. He didn't look gay. He liked baseball. And beer. And he'd seemed to like her.

"I didn't mean to give you the wrong idea." Zach grabbed Spencer's hands and squeezed them hard. "I've been having so much fun with you, and I don't want anything between us to end. It's just…no one knows. Especially not my dad."

The song morphed into a sped-up mix from something by the Glee cast, and a bunch of girls screamed. Spencer stared at Zach's soft, slender hands in hers. Something inside her turned over.

"Your secret is safe with me," she said, squeezing his hands hard. The proud, always-gets-what-she-wants girl inside of her still felt disappointed and embarrassed, but she also felt flattered and touched that Zach found her as fun as she found him. If their parents continued dating, maybe Zach would end up being the perfect quasi-sibling Spencer had always wanted. Maybe she should've been searching for a brother instead of a sister all along.

Zach jumped to his feet and pulled Spencer up, too. "Glad we got that straightened out. Now where were we?"

Spencer tossed her blond hair over her shoulder. She felt light and free as she sashayed through the crowd, but a presence behind her made her stop and turn. There, under the glowing Exit sign, stood a dark, hooded figure staring straight at her.

Spencer stepped back, her heart leaping to her throat. A split second later, the figure had turned away and melted into the crowd—anonymous, undetectable, but still dangerously close.