The year is 2030. The world is rebuilding from World War III. In Neo-Tokyo, plans are being made to hold the next Olympics in the "old city"--where, thirty-eight years before, the first of the bombs fell.
Kaneda and his friends, teenage delinquents, make an unauthorized motorcycle run into the old city to check out the old site. They encounter a terrified child, known only as Number 26, possessing extraordinary telekinetic abilities. During the encounter, the paranormal boy gravely injures Tetsuo, one of Kaneda's close friends. Then, he vanishes.
The next night, at Harukiya, a tough local dive, Kaneda attempts, unsuccessfully, to pick up a newcomer, Kay. In fact, she and her companion, Ryu, are part of an underground resistance group dedicated to learning what is happening in the old city and putting a stop to it.
Trouble ensues, and both delinquents and resistance fighters again encounter Number 26. Ryu attempts to reassure the paranormal boy, but Kaneda is anxious to punish him for injuring Tetsuo. As they argue, the mysterious soldiers pursuing Number 26 reach the scene, and a firefight results.
Then the ominous Colonel in charge of the covert operation appears with a secret weapon--Number 27, a crippled paranormal child named Masaru. Masaru astonishes the resistance fighters by addressing Number 26 as Takashi. Kay and Ryu had previously assumed that Number 26 was the Colonel's ultimate weapon--the as-yet unseen paranormal giant code-named Akira.
Kaneda provokes a crisis by pretending to threaten Takashi, who is exhibiting symptoms of drug withdrawal. Takashi responds with telekinetic upheavals. Kaneda is again separated from the resistance fighters, but he manages to intercept and hide a pill meant for Takashi, who is recaptured by the Colonel's men.
The next day, Tetsuo--who following his accident was taken to a hospital by soldiers--reappears in school, seemingly all right. However, during Tetsuo's treatment, the Colonel has learned the delinquent has great psychic potential.
Kaneda has a girlfriend in the school infirmary analyze the drug intended for Takashi. It is similar in substance to pills Kaneda and his friends take, but unbelieveably concentrated and powerful.
Determined not to let a new human weapon escape him, the Colonel goes to the school and collects Tetsuo.
Under the treatments of the Colonel's chief medical officer, Tetsuo exhibits powerful psychic abilities...and undergoes great pain.
Meanwhile, Kaneda, trying to spy on the Colonel and learn what is happening to Tetsuo, re-encounters the members of the resistance, and is brought back to their headquarters. Questioned by Ryu, he denies all knowledge of the stolen drug.
Kiyoko, another of the psychic children under the Colonel's control, announces to her master the disastrous news that Akira--who is asleep, and expected to remain so for some time--will awaken in the near future. Meanwhile, at the resistance hideout, Kaneda encounters a ghost-like apparition of himself, shouting Akira's name.
When the soldiers enter the resistance hideout in force, Kaneda and Kay manage together to escape to Harukiya, where the bartender agrees to shelter them.
Overwhelmed by pain, Tetsuo breaks out of the Colonel's installation, using his burgeoning powers to slaughter all who oppose him. Tetsuo takes control of the Clowns--a vicious motorcycle gang who are rivals to Kaneda and his friends--letting them live in return for the massive amounts of drugs required to stave off his agony.
Ryu meets with Nezu, a resistance leader, and they share new evidence on the scale of the Akira project.
A spy from the Colonel's organization learns of the Harukiya hideout, but he is caught and left for dead by a resitance fighter.
Yamagata and Kaneda's other friends come to Harukiya. Kaneda is amazed at the stories they tell, of Tetsuo's new powers and of his bloodthirstiness. He and Yamagata lead all of the local street gangs on a massive all-out attack to stop Tetsuo and the Clowns. Shortly after they leave, the Colonel, alerted by his informant, arrives at Harukiya and forces the bartender to tell him where the fugitives have gone.
Yamagata and his team corner Tetsuo in a warehouse. Most of the gang dies, and Yamagata tries to shoot Tetsuo. Kaneda reaches the scene in time to see Tetsuo brutally kill Yamagata. Enraged, Kaneda does shoot Tetsuo...who survives the deadly wound. As they fight, Tetsuo grabs the drug Kaneda had hidden.
When the Colonel arrives, Tetsuo swallows the drug, apparently dying of an overdose. A few minutes later, the terrible delinquent recovers, more powerful than ever, and the elated Colonel rechristens him Number 41.
Within one of 21st Century Neo-Tokyo's great city towers is a secret government project. Here, a volatile group of individuals is gathered. Most volatile of all is Tetsuo, haunted delinquent with murderous psychic power. The project's head, the Colonel, hopes Tetsuo can be used to counter an even greater threat...the as yet slumbering paranormal giant AKIRA. But three mutant children in the project sense impending doom in Tetsuo's presence. And two captives there--the anti-government agent, Kay, and Tetsuo's former friend, Kaneda--would do anything to see Tetsuo never unleashes his power again. All of these individuals are prisoners in a deadly chain of events, players in a mounting game of earth- shattering consequence.