From Possess and Ten author Gretchen McNeil comes a deliciously eerie science fiction–horror story in the tradition of Lisa McMann's Wake trilogy and the movie Sliding Doors—now in paperback!

Josie Byrne's life is spiraling out of control. And just when she thinks it can't get worse, she starts having dreams about a girl named Jo. Every night at the same time—3:59 a.m. Jo's life is everything Josie wants: she's popular, her parents are happily married, and her boyfriend adores her. It all seems real, but they're just dreams, right? Josie thinks so, until she wakes one night to see a shadowy image of herself in the bedroom mirror. Except it's not her at all—it's Jo.

The two girls are doppelgängers whose universes overlap every twelve hours at 3:59. Fascinated by Jo's perfect world, Josie jumps at the chance to pass through the portal and switch places for a day. But Jo's world is far from perfect, and the stuff of nightmares lurks around every corner. And when Josie finds herself trapped there, her life becomes more dangerous—and more deadly—than she ever imagined.

• Doppelgänger Romance: Josie's life is a mess, but her identical twin Jo has the perfect boyfriend. When they switch places, Josie gets a second chance at love—if she can survive the night.
• YA Thriller: A portal opens every twelve hours at exactly 3:59, connecting two worlds. But crossing over is a one-way ticket to a realm where shadowy creatures hunt in the dark.
• Dark Secrets: The promise of a perfect life is a lie. Jo's world is far from idyllic, hiding deadly secrets and terrifying monsters around every corner.
• Survival Horror: Trapped with no way back, Josie must fight to stay alive in a world designed to kill her.