A card game "Zenonzard" in which a human called a "Concord" and an ultra-high-performance AI called a "Codeman" fight as a team. While spirits are high for the upcoming world tournament, The Zenon, a mediocre high school student, Azuma Souta, is challenged by a mysterious woman, Irietta Rush, to play Zenonzard. Her aim is to reveal her true nature and participate in The Zenon.