Upon waking in a hospital, Minato Kiyomizu learns he has been in a coma for 203 days. A car accident has caused him to lose all memory of his middle school days. Eventually, he recalls his former glory in water polo and wishes to continue where he left off. However, embarrassingly aware of the massive disparity between his past and current self, Minato begins intensive rehabilitation, hoping to start anew—a life without water polo. Yet, on his very first day at Yamanami High School, Minato is promptly reminded of his past prowess and a promise he made. Soon after, despite being fully aware of his ineptitude, he joins the school's water polo club! While needing to relearn the sport's basics, he and his clubmates must recruit new members to reach the required seven-man roster. With that, Minato tries to rekindle his deeply buried talent for water polo—and become one of Japan's renowned players once again.