A rookie detective's friend is brutally murdered by the Japanese mafia, she must revenge for her and bring justice to the world, as an assassin.

KATE, a rookie detective, happens to blunder into a hit job in progress and see assassins. She is about to be killed for cleaning any witness by one of them, Gen, but he takes pity on her and makes her swear that she will never reveal their identities. Another day, as Kate's best friend is murdered by the Japanese mafia (Gondo's), Kate finds Gen to ask for her friend's revenge, but she is denied for the poor compensation she brings. Gen plus other assassins accept her wish which is also joining as an assassin in the condition with them. How will she be as an assassin and as a detective......? We find that each life is connected; like a "bond of justice" which comes from friendship and love among assassins.—production