Giant Killing is a Japanese manga series that revolves around East Tokyo United, ETU, a football team that is struggling in one of Japan's top leagues. After five straight losses, the team's morale hits an all-time low and they are losing favor with their fans. During their attempts to make a come back, the General Manager of ETU contacts an old friend of his, the eccentric Tatsumi Takeshi (voiced by Tomokazu Seki), who was a football player in his youth. After leaving his team, Tatsumi went on to manage FC Eastham, an amateur team in England, and lead them through the fourth round of the FA Cup. Hoping for the same results in Japan, the team attempts to work their way back to the top of the standings. Facing not only their own morale and teamwork issues, the team must also overcome playing against teams that have access to larger budgets as well as better players.