Seven years after the world freezes, humanity’s last survivors live aboard the Snowpiercer, a 1,001-car train divided by class. When a murder threatens the fragile order, tail-section leader and ex-detective Andre Layton (Daveed Diggs) is pulled into an investigation led by the mysterious Melanie Cavill (Jennifer Connelly). As tensions spark rebellion, betrayals, and power struggles, survival hangs in the balance. Across three thrilling seasons, new threats emerge, and the fight for control of the train takes unexpected turns.