Teenage assassins Mahiro and Chisato visit the coastal city of Miyazaki for a contract and a vacation when they unexpectedly cross paths with a legendary, bloodthirsty assassin who's looking to add to his kill count.

Chisato and Mahiro must pay four years of overdue fees or lose their membership in their assassin guild. They take part-time jobs, but find themselves in the middle of an armed robbery and being hunted by other assassins.

Baby Assassins is a thrilling action comedy that follows a group of high school girls in Japan who are recruited by a crime family to become assassins. The story revolves around their struggles as they balance their daily lives as students with their secret lives as killers. With a mix of martial arts action, comedy, and drama, Baby Assassins takes the audience on a wild ride filled with violence, friendship, and unexpected twists.