Reiji Kikukawa, who has a strong sense of justice, graduated from the police academy with the lowest score ever. He becomes a police constable, but is suddenly fired by the Police Chief due to "disciplinary" issues. In actuality, the firing is part of a carefully orchestrated plan to set him up as an undercover cop in the Yakuza.

A young undercover cop tries to get back with his former love, while unraveling the mystery behind the head of the police force. Meanwhile he has to protect the boss' daughter.

Reiji's final mission is to prevent the smuggling of 600 billion yen of drugs. For his mission, he gets on luxury passenger ship and he faces his strongest enemy to date.