On the island of Papeete in French Polynesia, Zebediah Killgrave, the Purple Man, lives the good life, using his powers of persuasion to turn the local rulers into his servants. His idyll is interrupted by a mysterious visitor who proves immune to the Purple Man’s powers and he snatches up the villain for use in a scheme of his own….
Manhattan: a disguised Sub-Mariner walks the rainy streets on his way to a meeting at the exclusive Four Seasons restaurant. Entering the dining room, his coat and hat are burned off by an energy blast from his host—Doctor Doom. Namor came because Doom mentioned a plan to free the Atlanteans from the tyranny of the surface-dwellers. Doom points out that no one in the crowded establishment paid any attention to the power blast—and reveals why. He wields a Psycho-Prism, powered by a single hair from the Purple Man, which gives him the ability to control the minds of others. He is now constructing a mammoth version of the Psycho-Prism which will enable him to rule the world. But there are three beings whose artificial nature means the Psycho-Prism has no effect on them; this is where Namor comes in. In exchange for attaching special discs to those three to make them susceptible to the Prism’s influence, Doom offers Namor rule of the oceans. Namor agrees….
In Hollywood, the "King of the Stuntmen" Simon Williams is being blown up for a World War I picture; when shooting ends for the day he heads to the West Coast Avengers’ compound as Wonder Man. There, Tony Stark has set up an experiment Simon has agreed to: in order to study the energy that makes up his body, Wonder Man will spend thirty days locked in a chemical bath inside a sensory deprivation tank. Despite his misgivings, he goes ahead with the deal—after all, as Tony says, what can happen in a month…?
Meanwhile, at Avengers Mansion in New York, Jarvis informs the Vision that he has a visitor—the Sub-Mariner, who has used the small Psycho-Prism to gain entry so he can attach Dr. Doom’s refractory disc on the android’s body. When Vision naturally resists, Namor, has the mind-controlled Starfox threaten to decapitate Scarlet Witch unless Vision submits. Seeing his beloved in danger, the android allows the disc to be placed on his body and the Psycho-Prism takes over his mind. Namor orders them to erase the record of the visit from the filmed record; one down…. The second target is Machine Man, who turns out to be easy: Namor merely commands his mechanic Gears Garvin to place the disc on him during repairs. Two down…. The third is Ultron, who is easily beaten and controlled by the stronger Namor. All three "problem" subject have now been dealt with….
Doctor Doom, meanwhile, visits his private island where he observes the progress on the giant Psycho-Prism with the Purple Man trapped at its center. The imprisoned villain shouts defiance; Doom approaches and removes his mask, standing face to face with the Purple Man, demonstrating that his will is so strong that Killgrave’s hypnotic powers are useless against Doom….
The West Coast Avengers are aware, however, of the happenings in new York since all records entered into the Avengers computers are accessible from both coasts. Investigation of a comment made by Namor on the tape leads them to Doom Island where they attack in force. Doom is surprised but his defense system and cadre of guards are prepared for the invading heroes. The Avengers take them on, until suddenly Doom orders his guards to allow the heroes to enter his stronghold. They find the villain in his control room where he permits them to witness his grand triumph—he activates the giant Psycho-Prism…and in a flash, the Avengers are confused by why they are there. Doom orders them to leave; they apologize for bothering him and meekly comply….
Two days later, Doctor Doom addresses assembled world leaders at the United Nations building in New York. He proposes himself for the position of Emperor of the Earth, and the leaders vote unanimously to give him the throne. Sub-Mariner approaches Doom about their bargain; Doom reneges and reveals that the small Psycho-Prism can control Namor’s mind—bringing the last strong-willed being under his command. The new emperor quickly uses his absolute authority to end wars, famine, injustice, crime, economic troubles, etc….
At the end of the thirty-day experiment, Wonder Man emerges from his deprivation chamber and wonders where Tony Stark is. He finds the industrialist busy converting the space shuttle into the Emperor’s private transport. Captain America and Wasp are redecorating the compound for the Emperor’s visit and Tigra is doing a charity benefit since there is no crime to fight anymore. A confused Simon turns on the TV and sees Doctor Doom being honored in New York; he warns the others—and to his horror they contact Doom and notify him that Wonder Man is a rebel (the Psycho-Prism has no effect on his artificial body) and try to capture him. Wonder Man manages to fight his way to freedom past his comrades and make it to a city—where the loyalist populace, warned of a traitor, mobs him. He vanishes into the sewers and makes his way to the movie studio where he dons an elaborate disguise to blend in. On the run, the depressed Simon has a talk with a blind woman who advises him to use what talents he has for the good of society; Wonder Man realizes he possesses one thing no one else in the world has: awareness, and with a new determination, he heads back for civilization. He researches the Avengers’ tapes of the incident and a close-up of the Psycho-Prism reveals the participation of the Purple Man. Reasoning he can snap his teammates out of their spells, he challenges Captain America to a fight, gets him in a headlock, and forces him to view films of the avengers’ earlier battles with Doctor Doom. The trauma forces Cap back to normal; Cap then conceives a plan to do the same to Iron Man, Wasp, and Hawkeye under the guise of testing a new educational computer, which likewise does the job. With this core team, Cap and Wonder Man are ready to take on Doom—but there is one snag: Hawkeye tries to rescue his wife Mockingbird but she resists and warns Doom of the new situation, ruining their chance at surprise. They assault Doom Island anyway, fighting their way past Doom’s tanks and robot army. The Emperor orders Namor to guard the Psycho-Prism with his life; Wasp enters the chamber and uses her sting to destroy the mini-prism around Namor’s neck but this does not release him from Doom’s control. She then shatters the glass wall, letting the sea pour in; Namor, his full power restored, is enraged at how he has been used. Watching from a scanner elsewhere, Doom allows his finger to hover over a button that will release nerve gas into the Psycho-Prism chamber, but, having grown increasingly bored with rule, he relents. Namor destroys the Psycho-Prism, apparently killing the Purple Man. With the destruction of the Psycho-Prism, the world returns to its miserable normal state. Doom escapes, a bitter Namor heads for the sea, and the Avengers are left to debate the morality of their act. Hawkeye concludes, "We’ve done mankind the greatest favor in history—or we’ve done it the greatest damage. And either way, that’s something we’re going to have to live with—for the rest of our lives."