Struggling writer Jake Mercer is driving through rural Montana, trying to escape the wreckage of his marriage and a past he can't remember well, when he stumbles upon Lucy's All Night, a swanky 1950s-style diner in the middle of nowhere.

The diner doesn't open until midnight.

The jukebox plays songs never played on the radio. The coffee never gets cold. The salt shakers are refilled with black crystals. A woman in Booth 3 cries over a slice of cherry pie before vanishing at 12:17 a.m., leaving behind clues that defy logic: a train ticket to a city erased from history, bite marks that don't match any known animal species, and a smell that reminds Jake of his grandmother's funeral.

Each night brings new rules, strange customers, and a growing suspicion that the diner isn't just a place but a punishment.

When Jake tracks down the real Lucy, now 92 and rapidly fading, she whispers the truth:

"We weren't serving food that night. We were serving time."

Now, Jake must piece together a decades-old mystery tied to an unsolved crime and confront the question he's spent his entire life avoiding:

Is he the restaurant's next cursed victim?

Or has the killer just returned?