The Avengers, sans Ant-Man, pursue Hawkeye and finally manage to corner him but they receive a summons from S.H.I.E.L.D., allowing him to escape in the confusion. Hawkeye is small potatoes, however, compared to the problem that the Avengers need to solve this time. As shown in the previous episode, a gigantic green dome has appeared around the Cube that is composed of pure gamma radiation. The doomed Hulkbuster squad was taken out by Emil Blonsky, the Abomination, and an unlucky team of S.H.I.E.L.D. agents were caught inside the dome when it appeared. Security footage shows them mutating horribly after their exposure to the gamma radiation, a fate that will befall everyone present soon enough as the dome is expanding; it is projected to hit a major population center in six hours. S.H.I.E.L.D. requests that the Avengers go into the Cube, accompanied by a handful of S.H.I.E.L.D. agents and a much-recovered and significantly more ripped Doc Samson.
We then cut to Hawkeye who is stalking Black Widow (not remotely what we meant) all the way to a HYDRA safe house where he proceeds to kick copious amounts of ass and ends up taking her prisoner. He can't take her back to S.H.I.E.L.D., since he's still officially a HYDRA double agent but he can take her to the Avengers.
Unfortunately the Avengers are having their own problems as they have to square off against the horrors unleashed by the gamma radiation dome. First they encounter the mutated S.H.I.E.L.D. agents, whom Samson believes can be returned to human form once they leave the irradiated area, and then a laundry list of gamma-powered villains under the command of Samuel Sterns, the Leader. In addition to their numbers, the villains also have their powers enhanced by devices that were originally produced by Samson to drain gamma energy but have been modified to do the exact opposite. Although the heroes come out on top, it was all a ruse to breach their gamma protection suits, as they find out to their horror when the Wasp begins to mutate as well.
The Leader gets his allotted evil gloating time for the episode before telepathically commanding his creations (including the Avengers' S.H.I.E.L.D. backup) to deal with the intruders. Black Panther breaks away from the group and leaves them to fend for themselves, but they soon realize that he has the right idea and beat a hasty retreat towards the generator for the dome. Thor and Samson break through the monsters and gamma-powered supervillains, only to find the device guarded by the Wrecking Crew. Thor is no match for them, now that they are enhanced, but he keeps them occupied long enough for Panther to destroy the generator, allowing S.H.I.E.L.D. to round up the escapees and turn everyone back to normal. So Once Again, the Day Is Saved, thanks to the Avengers.
The story continues in "Gamma World, part 2"
Tropes:
- Body Horror: All over the place. Gamma radiation lean towards resulting in mutations like the Abomination rather than the Hulk.
- Cliffhanger: The Avengers defeat the U-Foes and destroy the Gamma Dome generator in the Cube. However, The Leader and the rest of the villains relocate to Las Vegas to start a new Dome for his plans.
- "I Know You're in There Somewhere" Fight: Thor tells a transformed Wasp to remember who she is, and she does very briefly come to her senses before fully succumbing to her monstrous state.
- The Immune: Thor is the only one in the group who boasts about not needing protection due to his Asgardian blood, and is unaffected by the gamma dome. Samson was already affected by gamma radiation long before, so he doesn't transform much to his relief after his gamma protection suit was destroyed.
- Locked into Strangeness: Samson's hair has turned green after his exposure to Gamma radiation back in "Breakout, Part 1". Lampshaded by Cap, of all people.Captain America: Why does that man have green hair?
Iron Man: I have no idea. - My Greatest Failure: The Cube for Doctor Samson.Doc Samson: Look around, this is all my fault. Bruce warned me, and I didn't listen. My only concern right now is making this right.
- Painful Transformation: Anyone trapped within the gamma dome suffers this. Wasp in particular after her gamma protection armor was destroyed.
- The Quiet One: Black Panther. Lampshaded when his first line of dialogue comes halfway into the episode.Wasp: I forgot you talked.
- Quirky Miniboss Squad: The Leader has the distinction of having two in this episode: The U-Foes and The Wrecking Crew.
- Suspiciously Similar Substitute: Thor compares the Gamma monsters to Hulk.Thor: These creatures may share his origin, but they are pale reflections of the true Hulk.
Iron Man: That's a good thing, Thor. - Took a Level in Badass:
- Samson is a lot more muscular than when we saw him last.
- The Leader's Gamma experiments make for even stronger villains, such as the Wrecking Crew.
- Written-In Absence: Hank stayed behind in Wakanda to study the Vibranium.
- Xanatos Gambit: The U-Foes don't have to actually defeat the Avengers; they just have to disable their Gamma armor so they can be exposed to the Gamma dome.
- You Talk Too Much!: Black Panther's reaction to Vector's speech of being enhanced by The Leader's device after knocking him out from behind.
