The brilliant doctor is a former surgeon who had his hands cut off by a Yakuza boss, named Hamazaki, as punishment for saving the life of a rival gang member. The doctor decides to take revenge on Hamazaki by creating the ultimate assassin who will be able to kill him and his entire organization.
The young woman, named Mayumi, is a drug addict who is sold by her boyfriend to the doctor. The doctor trains her in martial arts, firearms, and survival skills, and implants gun parts in her body, including a gun barrel in her arm, a magazine in her leg, and a trigger in her ear.
Mayumi is given a mission to kill Hamazaki and his men. However, the doctor warns her that she only has 24 hours to complete the mission before the gun parts in her body cause fatal injuries. Mayumi must use her skills to find and kill Hamazaki before time runs out, and she must also overcome the psychological trauma of being turned into a killing machine.
The movie is a violent and gruesome action thriller, with graphic scenes of torture and murder. It explores themes of revenge, redemption, and the dehumanizing effects of violence.