The Incredible Hulk opens with a title montage detailing Bruce Banner’s origin: exposed to gamma radiation during an experiment at Culver University, Banner transforms into the Hulk and injures Betty Ross and General Ross. Five years later in Rio de Janeiro, Bruce manages his heart rate while working at a bottling plant. When his blood accidentally contaminates a beverage, General Ross sends commando Emil Blonsky to capture him. Banner transforms, defeats the team, and flees to Culver University to reunite with Betty.
After being attacked on campus by Ross using sonic cannons, Blonsky—injected with a low-dose super-soldier serum—is severely injured by the Hulk. Banner and Betty meet Dr. Samuel Sterns ("Mr. Blue") in New York, who temporarily cures Bruce's transformation but reveals he mass-produced Banner's blood. Military forces capture Banner, and Blonsky forces Sterns to inject him with Banner's blood, transforming Blonsky into the Abomination. A drop of gamma blood also causes Sterns' brain to expand.
As the Abomination rampages through Harlem, Banner convinces Ross to release him and jumps from a helicopter to trigger his transformation. The Hulk defeats the Abomination, stopping short of killing him when Betty intervenes, and escapes. 31 days later in Bella Coola, British Columbia, Bruce meditates, intentionally raising his heart rate as his eyes glow green with a smirk—revealing he has mastered his physiology to summon the Hulk at will. In a mid-credits scene, Tony Stark approaches General Ross in a bar to discuss putting a team together.