- Guy Pearce as Dr. Bruce Banner/Hulk
- Lou Ferrigno as Hulk (voice and visuals)
- Robert Carlyle as Dr. Samuel Sterns/Leader
- Ryan Reynolds as Wade Wilson/Deadpool
- Jeff Bridges as General Thaddeus "Thunderbolt" Ross/Hulkbuster
- Rachel Weisz as Betty Ross
- Ryder Strong as Rick Jones
- Kevin Sorbo as Lieutenant Emil Blonsky/Abomination
- Samuel L. Jackson as Director Nicholas Fury
- Scarlet Johannson as Natasha Romanoff/Black Widow
- Jeremy Renner as Clint Barton/Hawkeye
- Stan Lee as mutated military soldier (cameo)
For reference, fancast inspiration.
Harvard microbiologist and nuclear physicist Dr. Bruce Banner is taken in a military research project to recreate the 'Captain America Super-Soldier transformation' by gamma radiation particle acceleration. In the nuclear field test, while the experimentation process is going on, drunk teenager Rick Jones, interrupts, midst of the process. Banner makes the ultimate sacrifice by pushing Jones out of the field, and his exposure of gamma radiation transforms him into a monstrous green creature, with massively immense strength, he is dubbed the Hulk and is on the hunt of the military, especially General Thunderbolt Ross and Lieutenant Emil Blonsky with military super-agent Wade Wilson.
It has been a year, and Banner is in hiding in Norway, with the help of Rick Jones and Betty Ross. While in Norway, Banner collaborates with an Oscorp scientist, Samuel Sterns, and they discuss the gamma radiation science and Bruce is hoping that Samuel can resolve his alter-ego problems, however, Sterns, who is obsessed with human evolution, is taking advantage of him, by getting more information from him about gamma radiation, until at one point, Samuel cracks the code to gamma radiation 'Hulk' transformation. However, Emil Blonsky discovers that Samuel has been helping fugitive Banner and uses him to find out the location of Bruce. Samuel is taken in custody.
Thunderbolt Ross and his Hulkbuster Unit arrives in Norway, Stavanger, where they comprehend Banner. Banner turns into the Hulk and has a ferocious battle with the Hulkbusters, but Bruce eventually defeats all of them, however, he loses and is knocked down when he faces with Wade Wilson aka Deadpool, a fellow failed super soldier and prisoner brought as a last ditch effort to take down Hulk. Rick Jones is taken in custody, while Betty Ross is pardoned.
Back in America, Wade introduces himself and exploits that he is a mutant and was once a human experiment of the Weapon-X program, a classified operative of a mysterious alias who was hell-bent on creating his own army of mutants. Samuel Stern is forced into submitting the formula to recreate the Gamma Super Solder in order to heal Blonsky. He gives over the formula gladly, knowing the military would abuse it, buying him an escape route. Blonsky is in gamma radiation therapy, until, at one point, he heals, only to become another monstrous being like Hulk. Blonsky, now the Abomination, crazed with his superior strength, escapes the military base. The military spec ops and Deadpool quickly attempt to sustain the Abomination, even with Deadpool's regenerative healing factor and superhuman strength, the Abomination causes havoc around Queens. Samuel takes this opportunity to escape, taking the remaining Gamma formula. Thunderbolt, reluctantly unites with Banner to take down Abomination. The Hulk battles the Abomination before his is sustained in a hyperbolic containment chamber.
A worldwide backlash over the resulting destruction caused by both gamma monsters has suppressed the government and the international criminal activity monitoring organization SHIELD to overview the vigilancy and alignment of Banner and Blonsky. A month later, Samuel, now dubbed the Leader, has now created his own cult, revolving around human advancement and evolution and plans to transform everyone into superior beings (gamma beings). This causes Banner to reluctantly side with the military to defeat Samuel. Creating a gamma serum, Samuel experiments the serum on himself, and morphs into a metahuman with a hive-mind brain and slight mind manipulation abilities, dubbing himself the Leader.
The Hulk Corps (Samuel's cult of gamma superhumans) infiltrates Horizon Labs, an Oscorp experimentation research facility, in order to burglarize some materials for a grand and an unrevealed scheme. Hulk and Deadpool interrupt their plans, and take down most of the gamma superhumans, however, the Leader, uses his pheromone manipulation ability to forcefully make some Oscorp scientists hand him over some materials for his project. The Leader, cripples Deadpool and they escape.
After the event, investigating the burglarized materials, Bruce eventually deduces that Samuel is planning to turn all humans into gamma beings by releasing a chemical cloud containing gamma radioactivity from an Oscorp tower. Banner, decides to singlehandedly confront the brainwashed Wilson and Samuel, however, he is interrupted by SHIELD agents, Natasha Romanoff and Clint Barton, alias, Black and Hawkeye, respectively. The SHIELD agents reveal that they know of Banner's innocence and will accompany him on defeating the Leader. Hulk, the SHIELD agents, and Thunderbolt in his Hulkbuster Armor, comprehend the Leader who has activated a gamma cloud by nightfall and also has freed the Abomination from captivity.
The gamma cloud is dispersed and crazed gamma humans starts flooding different towns and streets of New York. Thunderbolt and the SHIELD agents take care of the gamma freaks in the streets while Hulk confronts the Leader at the top of the tower. The Hulk easily overpowers the Leader, however, the Leader summons his trump card, the Abomination, and the two monsters start brawling each other, before the Leader is knocked unconscious. Midst, Rick Jones and the recovered Deadpool prepare an antidote serum to replace the gamma infected cloud and Deadpool drags Banner and Blonsky to the land, so that they do not destroy the whole tower, giving Rick enough time to replace the gamma serum that is infecting the clouds with an antidote serum. Rick attempts to climb to the top of the tower to switch the serum, however, the Leader awakens, and starts shooting and interrupting him. Rick is mortally wounded but he is able to replace the gamma cloud with an antidote cloud, shortly before collapsing to the ruins of the tower, and dying. reversing every infected person back to normal in a limited range.
Meanwhile, Hulk and the Abomination who have ended up in a place beyond the antidote cloud range, and are not effected by the serum, are battling. The Abomination is able to defeat the Hulk and wound him badly. However, General Thunderbolt provokes Hulk and makes him unlock his savage transformation, his ultimate height of rage, and in this new transformation, the Hulk overpowers Blonsky and defeats him, ultimately Blonsky dies of suffocation, being trapped under the ruins of a building.
Banner reverts to his human form and is shortly going to be surrounded by the military, however, Thunderbolt knows that Banner is a good person, and intentionally lets him escape, telling everyone that he escaped by himself.
The military funds and organizes Rick Jone's funeral, while Bruce watches from afar while Betty, who was at the funeral, notices he is there, and the both nod to each other, declaring farewell. Deadpool temporarily disconnects the military in order to find out who was really behind the Weapon-X program, Thaddeus also takes a leave for a short period of time to recover from the previous events.
.In a post credits scene, Banner, who is in South Brazil, is surrounded by many SHIELD mercenaries, before being introduced to Nick Fury, director of SHIELD, who offers him help and immunity.
- Hulk would go on to be in SHIELD protection in the Avengers, where he became one of the seven members.
- Hawkeye would go on to do the same.
- Both Hulk and Deadpool were created in an attempt to re-create the success of Captain America, the wartime super-soldier. Weapon X is a mysterious organisation later explored in further films.
- Deadpool is a mutant. Mutants are rarer in numbers and such, more secretive in the FMCU2. They would later be explored in further movies.
- Stavanger, Norway, where Bruce spends the majority of the film, is a nod to one of the roots of Nordic mythology. Hulk even destroys a statue of Thor in his battle with the military.