Avengers: Endgame picks up after the catastrophic events of Infinity War, where Thanos used the Infinity Gauntlet to erase half of all life in the universe. Devastated by their failure, the remaining Avengers are struggling with grief and loss. Tony Stark (Iron Man) is stranded in space, and back on Earth, the surviving heroesβincluding Captain America, Black Widow, Bruce Banner, and Thorβare left to pick up the pieces.
In a stroke of hope, Scott Lang (Ant-Man) returns from the Quantum Realm and proposes an audacious plan: using quantum time travel to retrieve the Infinity Stones from the past and reverse Thanos’s snap. The Avengers reunite, including Stark, who initially hesitates but eventually joins after solving the intricacies of time travel. Together, they split into teams and journey to various points in time to collect the stones, with each mission coming with its own set of challenges and emotional confrontations with past events and loved ones.
After retrieving the stones and constructing a new gauntlet, the Avengers reverse the snap, restoring everyone who was lost. However, a version of Thanos from an earlier timeline discovers their plan and launches an attack on Avengers HQ. This leads to an epic final battle, as all the resurrected heroes, including Spider-Man, Black Panther, Doctor Strange, and the Guardians of the Galaxy, join the Avengers in a full-scale war against Thanos and his army.
In the climactic moments, Iron Man makes the ultimate sacrifice by using the Infinity Stones to obliterate Thanos and his forces, knowing the act will cost him his life. His final words, “I am Iron Man,” cement his legacy as a hero who saved the universe. The film concludes with Tony’s funeral, where the heroes pay tribute to his sacrifice. Steve Rogers (Captain America) later returns the Infinity Stones to their respective timelines and, choosing to live out a quiet life with Peggy Carter, passes his shield to Sam Wilson (Falcon), symbolizing a new beginning for the Avengers.