A ragtag group of intergalactic outlaws known as the Guardians are now recognized heroes after saving the galaxy. As they continue their spacefaring adventures, they struggle to keep their newfound family together while dealing with their personal demons. Peter Quill, the half-human, half-alien leader, still grapples with the loss of his mother and the mystery of his parentage. Gamora faces her troubled past with her villainous sister, Nebula, while Drax mourns the loss of his family. Rocket, the genetically engineered raccoon, battles his self-loathing and insecurities, and Baby Groot, now in a new growing phase, adds a complex layer of childcare to the group's dynamic.

Their journey leads them to a series of misadventures involving theft, bounty hunters, and cosmic threats. After a narrow escape from a high-stakes mission gone wrong, they encounter Ego, a celestial being who claims a connection to Peter, offering long-sought answers and a sense of belonging. As they venture into new territories of space, the Guardians must confront the challenge of trusting this new figure and the implications of his true nature. Simultaneously, old enemies become reluctant allies, and the group learns that the greatest danger may come from within.