Gaku Shishiya is the son of Kei, a former ace of the Japanese national volleyball team, and he himself was the star attacker of his middle school club. Despite this success, Gaku is uncertain if he truly belongs in the attacker position, haunted by the shadow of his father's legendary career. One day, Kei comes to watch Gaku practice and meets Noboru, a boy his son's age with extraordinary talent as an attacker. Impressed, Kei declares his intention to train Noboru to become the best volleyball player in Japan, effectively ending his relationship with his son. This fateful encounter shatters Gaku's world, but also ignites a fierce new resolve. He vows to prove his own limits as an attacker by mastering a unique style of volleyball he will pioneer himself, aiming to defeat both his father and Noboru. Set within the competitive world of Japanese youth volleyball, the story follows Gaku as he attempts to forge his own path and identity in the sport, distinct from his father's legacy. As the series progresses, Gaku faces the challenges of technical and mental growth, intense training, and high-stakes matches that will test his new philosophy against the traditional powerhouse style represented by Noboru under Kei's guidance. The ongoing narrative focuses on this central rivalry and Gaku's journey to define what it truly means to be an ace.