Taking the world by storm, the card game Cardfight Vanguard has influenced many to integrate card games into their everyday lives. Players of the popular game are called "cardfighters," and they frequently battle each other in card shops. The game has inspired many people, one of which is the quiet and timid Aichi Sendou who is often ridiculed and bullied by his peers. Whenever he feels down, he takes a glance at Blaster Blade—a legendary rare card given to him when he was young—and gains the motivation to move on with his life.
However, one day, school bully Katsumi Morikawa notices Aichi's treasure and snatches the card away from him. After a turn of events, Aichi soon discovers that the card is now in the hands of Toshiki Kai, a cardfighter who has become the strongest in town despite having only recently arrived. To make matters worse, Kai refuses to return the card unless Aichi defeats him in a cardfight.
Much to everyone's surprise, Aichi rises up to the occasion. As he musters up his courage and pictures himself winning this decisive battle, Aichi begins to find his way into the adventurous world of Cardfight Vanguard.