His name is Kuro, and he is a cat. He is owned by an elderly couple who lead a simple, easygoing life. However, because they are wealthy, thieves frequently attempt to raid their home. Each time, Kuro manages to fight them off, proving himself to be an excellent watch cat. One day, Kuro is shot with an arrow and abducted by Doctor Go, an evil scientist. Doctor Go transforms Kuro into a cyborg to assist him in his mission to conquer the world. Doctor Go attempts to control Kuro, but Kuro manages to escape. This infuriates the doctor, who feels that Kuro is ungrateful. With the help of Mi, another cyborg cat, he devises various methods to capture and kill Kuro. Kuro possesses a new, invincible cyborg body equipped with the latest hi-tech weapons. Yet, he also retains a warm heart, which is partly what makes this story so endearing.