In the Pacific Theater in the closing days of World War 2, the Invaders, on a mission to destroy a new solar-powered tank, battle a band of Japanese soldiers. Captain America—the Spirit of ’76, William Naslund, replacement for the original hero who is presumed dead with the first Bucky (hereafter Cap2)—is caught in the blast of the tank’s big gun and sinks into the darkness….
In 1954, the fourth Captain America (Cap4) and third Bucky crash into a garage to break up a gang of Commie spies in the Watts section of Los Angeles. Unfortunately, the madness caused by their exposure to an imperfect Super-Soldier Serum prevents them from seeing that the enemies they are clobbering are merely a group of pals at a friendly card game. Suddenly Cap falters, questioning the morality of their actions. When he goes outside to clear his head, reality warps around him….
1982 (the present): Captain America—the original, revived Steve Rogers (Cap1)—comes upon his enemy the Scarecrow robbing a bank. Fighting off the villain’s trained crows he pursues the Scarecrow’s getaway car; Cap launches himself at the windshield—and vanishes….
After falling through darkness, Cap1 finds himself in a chamber face-to-face with Mister Buda; Cap2 and Cap4 are in glass cylinders to either side. When Cap1 demands to know why he was brought here and who the other Caps are, Buda replies in such enigmatic terms that another figure chooses to step forward to explain. It is the third Captain America, Jeff Mace, the former Patriot (Cap3). He recaps his history, regretting the fact that he was never able to match the heroism of his idol, Steve. He is now dying of cancer and Mister Buda has chosen to alter history to give Jeff a second chance to be a hero. What Buda has done though is rewrite the past so that Adam II and his race of androids conquered the world in 1946 and are crushing humanity under their heel. The four Captains America can step in to liberate the world all over again. Cap1 is disgusted that Jeff Mace would welcome this turn of events and that Buda would make it happen. The arrogant Buda simply tells Cap1 to accept the situation and learn the lessons offered; he then drops the four Captains into this dystopia he has created….
Cap2 (Spirit of ’76) and Cap4 (1950s) find themselves in a desert area where hulking android guards are herding captive humans along in chains. These humans were not suitable for refitting as cyborgs so they are being taken to a Reconversion Camp where their brain energies will be added to the master computer. The two Caps rush in and defeat the androids. Cap4 heads off to find the Reconversion Camp while Cap2 tries desperately to explain freedom to the liberated captives; the android guards recover and capture him. As Cap4 is reconnoitering the Camp he is met by a, agent from the human resistance—who turns out to be a traitor and leads Cap into a trap where he is taken prisoner….
Cap1 (Steve) and Cap3 (Patriot) find themselves in downtown Washington. The original hero is annoyed by the younger man’s enthusiasm about their mission. The duo run into the Invaders, who turn out to be cyborgs in service to Adam II. After a scuffle, Cap1 is knocked out by Bucky, and Cap3, losing heart, surrenders….
At Castle Computronex (on the former site of the White House), Cap1 and Cap3 are brought before the android autocrat Adam II. The villain explains that the two other Caps have already been converted into cyborgs and they are next. Cap1 stands up to him in defiance, shaming Cap3 into attacking Adam II who allows the combat to continue. As they fight, Cap3 grows stronger, staggering his android foe with his blows—but it is because he is draining the essence of the original Captain America. He is then faced with a decision: choose glory…or sacrifice. He chooses sacrifice, and as the life energy flows back into Cap1, he is easily beaten by Adam II. Cap2, though now a cyborg, is inspired by Cap2’s example and is able to overcome his programming to attack Adam II—but he is easily defeated as well. Adam II engages the original Cap in combat, hoping to destroy humankind’s greatest symbol; Cap responds that he is not a symbol, that when anyone chooses the path of sacrifice and heroism they becomes Captain America. The villain then zaps Cap with an electric ray—but Cap’s words had an effect: the two converted heroes turn their new enhanced powers against their master—and an ordinary man, Jeff Mace, delivers the killing blow with his shield. Cap1 and Cap3 materialize in the presence of Mister Buda, and he questions Jeff as to the outcome. Jeff is at last free of his inner demons and can go on with life, perhaps even beating the cancer. As they are returned to their own time, Cap1 recognizes that his replacement is truly a Captain America.