Ji-yeon, a tollgate ticket girl, is frightened by a mysterious black car, which pays a bloodstained ticket fee at midnight. Her fear deepens after her colleague, Jong-sook, tells her that 12 years earlier a prisoner transport vehicle caused a traffic accident wherein all the prisoners involved died – and some of the corpses disappeared. Afterwards, a murder occurred near the tollgate on February 29th every four years. Soon, odd events become increasingly frequent, usually involving a doppelganger of Ji-yeon. When Jong-sook is killed on the fateful February 29th, Ji-yeon – with the help of two detectives – starts looking into matters herself.

Chul-Soo is the only son of a legendary thief family. He falls in love with Young-Hee who is a police officer. Her family is also a police family. To get her parents’ permission to marry, Chul-Soo undertakes an exam to become a police officer, but both families work to prevent their marriage.

A former agent from the North Korean intelligence and a senior member of the South Korean security services conduct a secret mission to prevent the breakout of a nuclear war on the Korean Peninsula.