Kokusai himitsu keisatsu: Kagi no kagi (国際秘密警察 鍵の鍵, International Secret Police: Key of Keys), also known as Key of Keys, is a 1965 Japanese comedy-spy film directed by Senkichi Taniguchi. It is the fourth installment in the Kokusai himitsu keisatsu series, a parody of James Bond-style spy movies.

Woody Allen used footage from Kokusai himitsu keisatsu: Kayaku no taru (国際秘密警察:火薬の樽, International Secret Police: Keg of Gunpowder), the third installment, along with Key of Keys, for his directorial debut, What's Up, Tiger Lily? In the film, the original dialogue is redubbed in English, transforming the plot into a comedic story centered around a secret egg salad recipe.