29 February

Ji-yeon, who works as a tollgate ticket collector, becomes terrified when a mysterious black car pays its toll with a ticket stained with blood at the stroke of midnight. Her anxiety grows when her coworker, Jong-sook, reveals that 12 years ago, a vehicle transporting prisoners was involved in a crash, resulting in the deaths of all the prisoners, with some bodies mysteriously vanishing. Following this incident, a murder has occurred near the tollgate every leap year on February 29th. Strange occurrences start happening more often, frequently involving a double of Ji-yeon. When Jong-sook is murdered on the ominous February 29th, Ji-yeon, aided by two detectives, begins her own investigation into the unsettling events.