The Forgotten Arm is the fifth album by singer-songwriter Aimee Mann with illustrations by artist Owen Smith. It was released by SuperEgo Records on May 3, 2005. It is a concept album, telling the story of two characters who run off with each other to escape their problems, but end up in more trouble than either of them could have imagined. The album reflects Mann's own boxing in its story and illustrations. The title is derived from a move in which one arm is used to hit the opponent, causing him to "forget" about the other arm, which is then used to deliver a harsher blow.