She wakes up on a stopped subway car with no memory - and the other passengers are vanishing one by one. Seventeen-year-old Mara wakes on a dead train with six strangers, none of whom can remember their names. Then the doors open onto impossible light, and the passengers start to disappear. A voice on the speaker always knows exactly how many remain. Mara is the only one finding clues: a name inked on her hand, a glove that reads NOT A TRAIN, a string of stolen numbers. Because she was never supposed to wake up in the car at all. She infiltrated Eidolon Labs under a false name to prove they killed her brother - and someone dosed her before she could expose them. To escape, she must outthink a system designed to make her forget why she came. But the most dangerous thing on the last train out may be her own missing memories. A propulsive YA thriller about grief, memory, and refusing to forget.