Hulk is being attacked by a group of army men in large tanks and helicopters. General Ross instructs one of his men to destroy Hulk. The man obeys by firing a missile at the Hulk, who deflects it with one of the army tanks as though the tank were a baseball bat and the missile were a baseball. The missile changes its course and heads back to the helicopter from which it was fired. The man in the helicopter quickly ejects himself, but the missile destroys the helicopter, which crashes into General Ross' tank and nearly kills him. A circular device flies up to the Hulk's face and he smashes it, and it is revealed that this battle was being viewed on video by Rick Jones, who explains that the circular device was a spy drone which recorded the entire battle, and spy drones used to be used by the military to record confrontations with the Hulk, supposedly painting an inaccurate image of the Hulk as a raging, deadly monster to the public and the media. However, Jones is now trying to use the spy drones to capture clips of the Hulk doing heroic deeds to show people his true, harmless intentions.
Jones then takes an elevator to a lower floor of his haven, followed by the spy drones, where he visits the Hulk, who is lifting weights. Hulk is not in a talkative mood. Rick explains that he is using the spy drones to make a web series about the Hulk in an effort to show the world that the Hulk isn't a monster. Hulk dismisses the idea, saying that the world will always see him as monstrous. One of the spy drones plays a news broadcast of J. Jonah Jameson speaking negatively of the "new menace," which was partially edited with voiceovers from Rick Jones to make it sound like Jameson was glorifying Hulk. The attempt does not comfort Hulk. Rick tries to convince Hulk that he shouldn't spend his entire life hiding in what is revealed to be an old military base. Hulk responds that, this way, he doesn't lose control of his emotions and can't hurt anyone. Suddenly, alarms go off. Hulk determines there is trouble half a mile away and hops into the elevator, destroying one of the spy drones in the process, not happy about the idea of his every action being recorded as part of a web series. He exits the military base and heads to Vista Verde, New Mexico, which Rick explains is where the Hulk was born and is the only place where residents have embraced the Hulk, sort of as a mascot. As Jones follows the Hulk in his jeep, his computer explains that there is a gamma storm generating hurricane-force winds in Vista Verde.
Hulk arrives in Vista Verde and immediately saves a little girl who is being blown away by the powerful winds, only to be confronted by a large team of army men with tanks, who command him to release the girl. Rick arrives and reminds the army men that the Hulk saved the girl. Hulk opts out of aggression and hands the girl to the men, instructing them to get her to safety. The army abides and the men depart. Hulk explains to Rick that the cause of this storm is a gateway to the Negative Zone in the sky, and he will solve the problem by "smashing" it. The Hulk lifts two cars and smashes them into each other, creating a powerful impact that sends a beam of energy blasting up to the gateway, but the gateway deflects the blast and it hits a nearby restaurant, which collapses on top of the Hulk. Annihilus is revealed to be responsible for this storm as he flies out of the hole.
Hulk explains to Rick that Annihilus is "top bug" of the Negative Zone, but has never had the power to invade Earth, and someone must be helping him. Annihilus rejects the opportunity to fight Hulk and instead unleashes a villain named Skaar to fight Hulk one-on-one. Rick acknowledges that Skaar looks like Hulk. There is a strange ticking device on the back of Skaar's neck, but Hulk and Rick fail to see it. Skaar and Hulk engage in a lengthy skirmish and wreck Vista Verde, but ultimately Red Hulk arrives in a plane and fires a missile that sends Skaar hurtling off into the distance. Red Hulk teases Hulk about not being able to defeat Skaar alone, but the Hulk doesn't engage Red Hulk. He mutters an insult and proceeds to walk away. When Red Hulk asks Hulk for words of gratitude after being saved in battle by Red Hulk, Hulk turns around and delivers a powerful blow to Red Hulk's face, and he is hurtled miles away in the opposite direction in which Skaar was hurtled.
A clip incorporated into Rick's webcast shows Red Hulk explaining that he is General Ross but became the Red Hulk so he would have more power to catch the Hulk.
Hulk reunites with Red Hulk and the two locate Skaar (off-screen) and bring the unconscious supervillain to Hulk's secret gamma base. Red Hulk makes a few nostalgic remarks about the gamma base and the machinery and explains that he tracked the storm to Vista Verde, figuring the Hulk and Rick would need some assistance handling the problem. Hulk places Skaar in an anti-gravity chamber. Somehow, Skaar manages to escape the anti-gravity chamber, which Red Hulk claims was escape-proof, within seconds of awakening. He grabs a nearby gamma blaster and fires it at Red Hulk. Skaar then begins firing stray blasts, destroying the gamma base. Hulk throws Rick out of the way and tries to take on Skaar, but is hit by gamma blasts. Skaar blasts a hole in the wall and escapes. Hulk recovers from the gamma blasts and gets back on his feet. Hulk explains that Skaar's gamma energy got him through the Negative Zone portal, and the gamma cannon which he stole will also allow Annihilus to get through. Red Hulk realizes that Annihilus planned Skaar's capture, so Skaar could be taken back to the gamma base and find some gamma technology to allow Annihilus to get through the portal. Hulk and Red Hulk go after Annihilus, but Hulk forces Rick to stay behind for his safety by placing the cylindrical tube from the broken elevator (destroyed by blasts from the gamma cannon) over Rick, trapping him.
As soon as Hulk and Red Hulk leave, Rick searches for a way to escape. He sees a hammer high on a shelf and manages to ram to scoot the tube over to the shelf and knock the hammer inside the tube. However, he also unwittingly knocks a time bomb next to the tube. Before Jones has a chance to use the hammer to break out, the bomb blows up the tube. Rick hops in his jeep and speeds after the hulks.
Just as Rick arrives at the portal, Skaar fires the gamma cannon at it, allowing Annihilus and his horde of inter-dimensional bugs to enter Earth. Hulk and Red Hulk arrive and jump out of their plane, landing right on top of Skaar and rendering him unconscious. Hulk proceeds to fight the horde. Red Hulk uses the gamma cannon to fire at the horde, almost hitting the Hulk as well. Soon, the cannon runs out of power and, while it is recharging, Skaar awakens and attacks Red Hulk. Skaar manages to knock Red Hulk unconscious. Rick drives the jeep right into Skaar and the gamma cannon. Skaar is hurtled into the distance, but Rick loses control of the jeep because the gamma cannon is under it and almost falls off a mountain. Hulk manages to catch the jeep just in time and recognizes, in a clip added to Rick's webcast, that Rick saved him, but also expresses that he fears something happening to Rick because of him. Suddenly, the gamma cannon explodes. Hulk grabs Rick and evades the full impact of the blast, but Rick is still injured. The Negative Zone portal is collapsed by the blast, and the horde of bugs is destroyed, but Skaar and Annihilus manage to escape in time, with Red Hulk in their hands.
Rick survives the blast and the spy drones manage to capture the footage of the battle on video, providing proof that Hulk is not evil. However, as Rick is laying down resting back at the gamma base, he suddenly starts to feel ill and his eyes glow a bright shade of green.