Attacker You! chronicles the life of a 13-year-old girl, You Hazuki (nicknamed "Mila", "Jeanne", or "Juana" in Western renditions), who is brimming with ambition and vitality. After moving from Osaka to Tokyo to live with her father Toshihiko, a cameraman recently returned from Peru, You attends school with her younger brother Sunny who has a crush on her and emulates her every move. She develops a love for volleyball and aspires to represent Japan in the 1988 Seoul Olympics as a part of the national women's volleyball team. Her mother is absent from her life.