The third season of Marvel's animated series "What If...?" premiered on December 22, 2024, on Disney+. It is the final season of the series and explores alternate timelines in the Marvel Cinematic Universe (MCU), showing what would happen if pivotal moments occurred differently. Season 3 features classic characters like Captain America/Sam Wilson, The Winter Soldier/Bucky Barnes, Hulk/Bruce Banner, Captain Peggy Carter, Agatha Harkness, Shang-Chi, and more. It includes eight episodes released daily until December 29, 2024. The season is directed by Bryan Andrews and Stephan Franck, with Matthew Chauncey as head writer. Jeffrey Wright returns as the narrator, the Watcher.

The season is noted for traversing new genres and bigger spectacles with incredible new characters. However, some fans find it uneven, with fewer traditional "what if" scenarios than previous seasons and some episodes focusing more on origin stories or character arcs than alternate realities. Despite mixed reactions, it offers a concluding adventure through the multiverse as part of the MCU's Phase Five.

In summary, "What If...?" Season 3 is the concluding season that delves into alternate MCU stories with familiar characters, providing fresh and varied storytelling experiences.