In this epic conclusion to the Infinity Saga, the surviving Avengers try to undo Thanos' terrible act from "Avengers: Infinity War," where he wiped out half of all life in the universe. They come up with a daring plan involving time travel to significant events from previous Marvel films to gather the Infinity Stones and reverse Thanos' snap. Along the way, they face old and new enemies, leading to epic battles and heartbreaking sacrifices. The film brings the original Avengers together one last time and provides an emotional closure for many beloved characters.