City Hunter Ryo Saeba's new client is Emi, a stage star who is looking for her long lost brother. But soon after starting, they are attacked by an international criminal mastermind known as the Professor, and it becomes clear that the case is going to be more exciting than just a sappy reunion. When someone of the Professor's caliber is in town, the police get worried – for a reason. But what is his real purpose for coming to Tokyo, and what is his connection to Emi? Ryo Saeba and his friends are once again in the thick of the action, and the fates of the city and Emi lie in their hands.