The city of Sternbild is home to many people of different races, backgrounds, and those who are called Next. Next are people who possess special powers. They are the superheroes who protect peace within the city.
The story mainly focuses on veteran hero Kotetsu T. Kaburagi (aka Wild Tiger), who is assigned a new partner -- a young man named Barnaby Brooks Jr. Barnaby and Kotetsu usually have trouble working together as they have conflicting opinions on how a superhero should act. Kotetsu is determined do what's best for the people, while Barnaby took up superheroing in the hope of one day discovering his parents' murderer.