|A 16-year-old boy encounters a time slip and is transplanted in a future world. The boy, called "Ryu Urashima" in the series, completely loses his memory and even forgets his own name, as he is time slipped. Ryu becomes a police detective in the future world and begins his new life with his cynical colleague, Claude Mizunuma, known as "Claude". Ryu, though bewildered with the new surroundings, challenges his new job to beat the evil called "Necrime Empire". Claude, an elite detective, helps Ryu although he trifles with him for his lack of knowledge about his new world. However, Ryu, with his formidable fighting spirit, tries to adjust himself to the new circumstance and gradually becomes a good cop surprising Claude now and then. The series depicts the adventures of these two young men and beautiful woman police, Sophia.