Tetsuo, the son of a bicycle shop owner, and his sister Hanako rescue Megumi Kuroki and Kiyotaka Sawada from a gang of bikers. As a thank you, they are invited to Kiyotaka's home. The siblings, who fell in love at first sight with Megumi and Kiyotaka, hope this will be the perfect opportunity to be alone together. However, the Sawada family is the home of the president of a major bicycle manufacturer, who brought down Tetsuo's father, Taichi, from his position at the company. Hanako soon develops feelings for Kiyotaka, and Tetsuo, wishing for his sister's happiness, fights against pressure to prevent their arranged marriage. Meanwhile, Kiyotaka's father, Ryuichi, the company president, invites Tetsuo's mother, out to apologize for his past treatment. The two eventually disappear. Tetsuo and Hanako search for their mother but find only Ryuichi, who has been burned beyond recognition and Shizuko is missing. The key to uncovering the truth lies with Taichi's sister, Sumire, but...