The Thing is posing for a sculpture for his girlfriend Alicia Masters in her apartment when suddenly they are interrupted by the arrival of an alien being calling himself Proja. He explains that he has come to examine the Thing and determine his strength. Impressed by Ben's physical shape, Proja explains that he is seeking combatants to fight his master, the cosmic being known as the Champion. Ben is upset by this intrusion into his life and is uninterested in the offer and tells Proja to leave. However Proja teleports away with the Thing when he tricks Ben into shaking his hand. In Chicago, Donald Blake climbs to the roof of his practice in order to change into his alter ego, the Asgardian thunder god known as Thor. Soaring across the city, Thor is also approached by Proja. In Washington, D.C., Doc Samson is interrupted during a session with a patient. Proja later also recruits the Hulk, the X-Man known as Colossus, the Sub-Mariner, Wonder Man, and Alpha Flight's Sasquatch. While at the Plaza Hotel, the Vision and the Scarlet Witch are interrupted by the arrival of Proja. Proja is about to recruit the Vision into this battle royale until he discovers that the Vision is an artificial being, disqualifying him from being selected to battle the Champion. Proja then teleports away before the Scarlet Witch can stop him with a hex bolt.
Elsewhere, those forced into being taken by Proja find themselves materialize in a strange alien gym. While the assembled heroes try to make sense of their situation, the Sub-Mariner attempts to break free. Smashing through the wall he quickly discovers that they are within a massive ship that is suspended in an empty void. Suddenly they are joined by the Champion who teleports into the room and announces that they will all have a chance to battle him in the arena. The Champion explains how he goes from world to world battling the strongest beings on a given planet for the thrill of the fight and prove himself as the undisputed champion of the universe, boasting that none have survived to fight a second round against him. When the assembled heroes try to rush the Champion all at once, he is able to deflect them back with the Power Primordial, the source of his strength. The Champion then informs them that they will begin training and summons personal trainers for each of the combatants.
Meanwhile back on Earth, Alicia has summoned Mister Fantastic and the Invisible Girl to help her rescue Ben. Reed examines Alicia's apartment for residual energy left over from Ben's abduction and is troubled to learn that the energy levels involved are on par with Galactus. While at Xavier's School for Gifted Youngsters, the X-Men return to their leader Professor X after their search for Colossus proved unsuccessful. When Cyclops suggests that the disappearance could be tied into some kind of anti-super-hero conspiracy, Xavier believes that the disappearances of heroes of great strength is something more than that. Back aboard the Champion's ship the training has begun. While both the Hulk and Thor excel in training, Doc Samson fails in a basic test and is returned to Earth, as is the Sub-Mariner when he refuses to comply. Also doing well in their training are Colossus, Wonder Man, Sasquatch and the Thing. As the training continues, Proja appears at the Daily Bugle and other newsmedia outlets to spread the word of the coming battle, generating plenty of buzz world wide. The match is organized to take place at Madison Square Garden. Tickets sell out quickly and soon bets are placed on who will win the match, while at Avengers Mansion the gathered members of the Fantastic Four and the Avengers debate on how to handle the situation.
Soon it is time for the big match and the remaining competitors are teleported to the ring, which is contained under a protective dome surrounded by a sold out audience. The first battle is between Thor and Champion. As the battle is about to begin, Cyclops and Wolverine attempt to penetrate the barrier to free Colossus, but find that neither of their abilities can breach it. Soon the battle begins, but when Thor attempts to use Mjolnir in battle he is disqualified and teleported away. Next is the Hulk, who rips through his gloves and tries to attack the Champion with his bare hands. Dismissed as a savage, the Champion also teleports the Hulk away. Next up is the Sasquatch, who is the first combatant to play by the Champion's rules, but is knocked out only after a few blows. The next match is Colossus who tries to put all his effort into battling the Champion is beaten so badly he needs to be taken away in a stretcher. This is followed by a match against Wonder Man who quickly loses his temper and tries to subdue the Champion by ripping up the floor of the arena floor, only to be disqualified and teleported away. With the fate of the world hanging in the balance the Thing is the last combatant left.
Ben refuses to give up, no matter how many times the Champion knocks him down, the Thing just continues getting up. Battered and bleeding the Thing begins to earn the respect of the Champion for not giving up. When Ben later charges at the Champion and grabs him around the waist, the Champion decides to continue the fight despite this being against the rules. Although the Thing manages to land some good punches in, he is knocked aside by the Champion and cannot get back up within the ten count. As the Champion is awarded his belt he is about to determine the fate of the Earth when he notices that the Thing is still struggling to get to his feet and continue the fight. Seeing that his opponent is willing to crawl on his hands and knees to continue the fight impresses the Champion so much that he decides to spare the Earth, suggesting that in time perhaps it will create a warrior that can defeat him in the ring. After the Champion teleports away the Thing collapses to the floor again, but he is still pulled up to his feet by his friends and allies who are celebrating Ben's apparent victory against the Champion.