Tetsuo Shima is a central character in the anime series and manga 'Akira'. Initially an insecure and troubled teenager, Tetsuo's life takes a dramatic turn after he gains immense psychic powers following a motorcycle accident. As his powers grow, they become increasingly uncontrollable, leading him down a path of destruction and chaos. His transformation and struggle for control serve as the catalyst for the series' events, ultimately leading to a climactic confrontation with his former friend and gang leader, Kaneda. Tetsuo's journey explores themes of power, identity, and the loss of humanity.