The Espers are a trio of psychic children (Kiyoko, Takashi, and Masaru) who have been government test subjects for a secret ESP project started by the government. They are the supporting characters of both the anime and the manga.
The Espers are a trio of children who were a part of a secret government project designed to acquire psychic powers and use them for personal benefit. However, after Akira's demise following a devastating psychic explosion that destroyed the original Tokyo, the project was terminated for at least thirty-one years and the Espers were kept in isolation to keep any information from being leaked. They wield a variety of psychic powers that are weak compared to those of Akira and Tetsuo, but are still strong enough to overcome a normal human being when combined. Although the Espers are children, their bodies take on a wizened appearance; the reason is because of years of being experimented on and taking special drugs designed to inhibit their psychic growth.
The Espers are close friends with each other and share a psychic link that enables each one to know their thoughts. They are very compassionate, selfless and caring, and they look out for each other and others' wellbeing, but their perceptiveness make them able to discern whether a person harbors hostile thoughts and intentions. They do not like fighting, but will go and fight if one of them is threatened in some way or if someone is destructive enough to cause death. As the drugs administered to them have inhibited their physical and mental growth, the Espers act like children and are thus innocent and childlike, such as their fear of blood; however after Tetsuo arrives they mature incredibly and act out their way to sacrifice themselves for the greater good.
Due to the experiments by the government, the Espers hold a variety of psychic powers which are weak compared to more powerful psychics like Tetsuo and Akira , but are very well-developed. When combined, the Espers' powers are able to overcome a normal human being, but it is how they use it that is important in deciding the outcome of the final battle.
The Espers came together when Takashi, Masaru, and Kiyoko developed psychic powers and were taken to the Nursery with the original intention to develop their potential for political purposes. They met and befriended each other and Akira, but were left behind under the care of Colonel Shikishima and the scientists when Akira transcended to a godlike existence and destroyed the original Tokyo in the process. To prevent a future psychic explosion, the Espers were fed drugs to inhibit their developing powers, with the side effects of suffering physical impairments - Kiyoko eventually became bedridden and Masaru was afflicted with polio. The drugs also inhibited their physical growth but they aged along with everyone else, appearing in the early 40's.
Takashi is kidnapped by a member of a resistance group who thought he was Akira, but it failed when the member escorting him was shot by shock troops and Takashi, in full view of his death, was severely traumatized and his psychic powers caused havoc among the gathering crowd. While wandering around on the highways in the old part of Tokyo, he came across Tetsuo and nearly got run over by him when he used his psychic powers in self defense, causing Tetsuo's motorcycle to explode and severely injuring him. Takashi is shortly found by the Colonel and Masaru, who take him back to the Nursery.
A little later, Kiyoko predicts the fall of Neo-Tokyo; Tetsuo and Akira are involved. In fear the Colonel instructs the scientists to eliminate Tetsuo, who is revealed to have innate psychic powers himself, if he gets out of hand. When they learn of Tetsuo's rapid development, the Espers disguise themselves and attempt to assassinate him in his hospital room but they fail when they are scared by the sight of his blood and their identities are revealed. In retaliation Tetsuo causes a bloody rampage throughout the hospital in an attempt to find them - when he does he fights the Espers intending to kill them, but is stopped by the Colonel and only manages in leveling the Nursery and scarring the Espers. When Kaneda and Kei arrive to rescue him, Tetsuo turns on Kaneda and tries to kill him but is stopped again, this time by Kiyoko, but he extracts information about Akira from her and flees via teleportation.
The Espers shortly discover that Kei is a medium capable of using their powers, and so they decide to use her to prevent Tetsuo from reaching Akira. This also fails as Tetsuo is more powerful than her and the three combined, but he eventually discovers that Akira had been dissected and put in a cryogenic chamber. They appear again when they hear that Akira is in the Olympic Stadium and go to contact him for help as a last resort against Tetsuo, who has since mutated into a monster due to his own powers because of outside circumstances and his battle with a vengeful Kaneda. Akira appears and absorbs Tetsuo through another explosion, but unwittingly takes Kaneda with him. Over the objects of Masaru and Kiyoko, Takashi goes into the explosion to save Kaneda, but his friends decide ultimately to help him also and teleport Kaneda back to Neo-Tokyo before joining Akira.
The Espers are among the six remaining test subjects of a secret parapsychology project sponsered by the government - the others are a small boy named Akira, Lady Miyako, a blind clairvoyant who became the leader and high priestess of a popular temple, and recently Tetsuo Shima, a bitter teenage biker with powerful telekinetic abilities and an inferiority complex.
In the original project the government sought to control their developing powers and use them for personal benefit; many have died during the experiments, but some survived with physical handicaps. The project failed when Akira lost control of his powers and caused a tremendous explosion that obliterated the original Tokyo, which many mistook for an atomic bomb and started World War III. While Akira was sealed away wholly in a cryogenic chamber underground, which stopped his biological aging, the Espers lived on as children with aging bodies.
Takashi was kidnapped from the Nursery by a resistance group, but escaped and ended up wandering around in Neo-Tokyo. He encountered Tetsuo on the highway where he was almost run over by his motorcycle but caused it to explode in an innocent gesture of self defense. He later encounters Kaneda, the leader of the Capsules biker gang, and when the Colonel and Masaru arrive to retrieve him, Takashi's powers were already going out of control and causing havoc, leading to a standoff. He is eventually taken back to the Nursery and restored to normal.
Later Kiyoko, another Esper, predicts that Akira is going to rise and destroy Neo-Tokyo, with Tetsuo's involvement. She bands together with Takashi and Masaru to kill Tetsuo to prevent this from happening by possessing Kei, a female terrorist and resistance member, but are hindered when the Colonel intervenes. The Espers eventually encounter Tetsuo, who arrives and, upon recognizing Takashi from his motorcycle accident, attacks them but is attacked by Kei and his friend Kaneda, who tries to shoot him with a laser gun. Tetsuo escapes, and Kei questions Kiyoko about Akira before leaving with Kaneda.