Captain Colter Stevens, played by Jake Gyllenhaal, finds himself in a surreal and confusing situation when he wakes up in the body of a man he doesn't know. He's trapped in a dark, enclosed space that he later learns is a metallic capsule. He's contacted by a woman named Goodwin (Vera Farmiga) and a man named Rutledge (Jeffrey Wright), who explain that he's part of a top-secret program called Source Code, and his task is to find the person responsible for a terrorist attack on a Chicago commuter train.
Stevens discovers that he's reliving the same 8 minutes of the train ride over and over again. Each time he relives it, he discovers new clues and gains more insight into the situation. He interacts with the other passengers, trying to gather information and piece together the events leading up to the attack.
Throughout the film, Stevens struggles to come to terms with his situation and begins to form a bond with one of the passengers, Christina (Michelle Monaghan). He becomes determined to save her and prevent the attack from happening.
As the clock ticks down on his mission, Stevens must make difficult choices and face unexpected challenges. He discovers that there's much more to the Source Code program than he initially thought, and the consequences of his actions have far-reaching implications.
Source Code is a tense, action-packed thriller that explores the nature of identity, memory, and the consequences of our choices. With a talented cast and a gripping storyline, it keeps the audience on the edge of their seats until the very end.