The full story
Bruce Banner exists in a state of perpetual exile, five years removed from the gamma radiation accident that made him both more and less than human. The Hulk emerges when his heart rate climbs—rage, fear, passion all become potential triggers.
In the favelas of Rio, Bruce works in a bottling plant, practices meditation, wears a heart rate monitor like a tether to humanity. He's searching for a cure through correspondence with a mysterious scientist called "Mr. Blue." When a drop of his blood contaminates a bottle, it leads General Ross—Betty's father, the man who views the Hulk as military property—right to him.
Ross recruits Emil Blonsky, a soldier at the end of his prime who sees the Hulk as everything he's losing: power, relevance, dominance. When the operation fails and the Hulk tears through Ross's forces, Blonsky doesn't respond with fear. He responds with hunger. He agrees to be injected with a variant of the super-soldier serum, becoming addicted to the very enhancement that will destroy him.
Bruce and Betty reunite, though the years apart weigh on them and Ross won't leave them alone. When Blonsky, now enhanced, faces the Hulk directly, the encounter leaves him hospitalized but alive—and more obsessed. A student films the battle, and suddenly the Hulk is viral, mythologized through shaky footage and fear.
In New York, "Mr. Blue" turns out to be Samuel Sterns, a scientist who has been replicating Bruce's blood. The treatment works, briefly, but Bruce is captured before they can confirm the cure. Blonsky, mentally unraveling from the serum, forces Sterns to give him more—combining super-soldier enhancement with Bruce's gamma-irradiated blood. The result is the Abomination: bigger than the Hulk, stronger, but without Bruce's restraint or humanity.
The Harlem battle forces Bruce to become what he's spent years fleeing. He jumps from a helicopter, betting his life that the fall will trigger the transformation. The Hulk that emerges fights not just for survival but for Betty, for the civilians trapped in Abomination's path. When he has Blonsky beaten, choking him with a heavy chain, Betty's voice pulls him back from the edge. The Hulk can choose mercy.
The film ends with Bruce in British Columbia, meditating as his eyes flash green—no longer trying to cure the Hulk, learning instead to live with him. In the final scene, Tony Stark approaches General Ross, recruiting him for something bigger.