Tetsuo’s early years are unknown. Flashbacks reveal he may have been an orphan. We first know of him as a student in a school for delinquents in NeoTokyo, Japan. He was part of Kaneda's gang of trouble-making bikers.
One night while trying to catch up with his gang he nearly collided with an escaped government experiment, a young boy with the face of an old man. The boy through his use of psychokinesis was unharmed but Tetsuo was left injured in the accident. When the secret military arrived, they found only Tetsuo and abducted him presumably for security reasons.
While at the government research facility, Tetsuo underwent some very peculiar “tests”. The nature of these tests were unknown but later that night in his room, he began to have vivid surreal dreams and exhibit psychic power including feats of telekinesis.
Tetsuo gained his telekinetic ability from coming in contact with one of the other telekinetic human being.His powers alter greatly because of government test and having to fight others out of his mind which cause them to go out of countrol.
He eventually establishes himself as a ruler over the renegade society of teenagers in old Tokyo. He supplied his society with experimental “pills” that caused each person to manifest some sort of psychic ability.
He finally was defeated by his old friend Kaneda, the experimental children, and Akira.
When Tetsuo's arm is disintegrated by the SOL laser, he reconstructs his arm via telekinesis from various metal parts he found.
Tetsuo’s power grows significantly over time. His control however seems be unable to keep pace with his power. When he is emotionally charged or hurt, his body contorts and balloons out of control, psycho metabolically mutating into an amorphous fleshy blob.
While out of control, Tetsuo inadvertently kills his girlfriend, Kaori, crushed within his flesh.
Tetsuo is known for his disdain for authority higher than his own. Years of being “not good enough” has grown an inferiority complex within him where he is constantly trying to overcompensate with displays of rebellious behavior. He compulsively tries proving himself first to his biker gang peers then as he manifests psychic abilities to the rest of the established world.
Psychokinesis – He has the ability to move matter and energy with his mind. While he hasn’t shown the ability to create psychokinetic explosions like Akira, he has been seen to rend metal objects of up at least 50 tons.
Teleportation - Tetsuo teleports once during the movie when he finds out where to go to find Akira. He escapes from the facility he was being held in this way. In the manga however he is constantly seen teleporting.
Flight – Psychokinetically propelling himself through the air he can fly at incredible speeds. He has been seen to fly up beyond the atmosphere to the level of Geo-synchronous orbit of satellites.
Telepathy – He has been shown to be able to hear the thoughts of the experimental children (other psychics) for miles away.