She sat in the passenger seat of her dad’s car, with Hallie at the wheel. Hallie had just gotten her license and their mom worried about her driving without a grown-up, but Maren needed a ride home from dance class and everyone else was busy. Maren had promised to keep an eye on her sister’s speed and check for hazards and bad drivers along the way.

“And I know Ms. Marigold said no tights with runs in them, but it was just a tiny hole,” said Maren, still upset about the stern talking-to she’d gotten after class. It wasn’t her fault she’d tripped in the parking lot on her way inside.

“Hmm,” said Hallie, flicking on her blinker.

“Are you even listening to me?” said Maren.

“Uh huh,” murmured Hallie.

“You’re not listening to me,” said Maren.

Hallie sighed. “I’m concentrating on my driving.”

“You can hear and drive at the same time.” Maren picked at the hole in her tights, which had grown from the size of a pencil eraser to the size of a quarter. “What’s going on with you lately?”

“Nothing.” Hallie’s voice was falsely bright.

“I don’t believe you,” said Maren. “You’ve been weird for a while now. Jumpy and secretive and stuff. I know you think nobody notices, but I do.”

“Aren’t you quite the little detective.” Hallie’s tone was unusually snide. Maren’s fingernail snagged through her tights, making another hole beside the first one. She tried to ignore the sting of her sister’s words and pressed on.

“Do you have a secret boyfriend or something?”

Hallie rolled up to a red light beside the marina where all the fishing boats docked. “No.”

“A secret girlfriend?”

“No.”

“Are you being tailed by the FBI because a kind, yet vaguely suspicious nuclear physicist asked you to hold on to her secret files and then disappeared?” Maren made a show of peering in the side mirror to see if anyone was following them.

“No.” Hallie didn’t laugh like she was supposed to, and a bolt of nerves shot through Maren. It wasn’t like Hallie to keep secrets from her.

“What is it, then?” she whined.

“I told you, it’s nothing.” Hallie inched toward the red light. Their mother always waited at this intersection to make sure the other traffic had stopped before going through. She always repeated the same warning to Maren and Hallie: Be careful here. People can’t see the traffic lights well in the late afternoon sun. Always wait until it’s safe to go.

Maren was supposed to remind her sister of all these things. Her dream-self mouthed the words, but her voice made no sound.

The light turned green, and Hallie stepped on the gas.