Marvel announces Avengers: Doomsday to open Dec 18 2026, starring Robert Downey Jr. as Doctor Doom

Marvel Studios confirmed that the upcoming blockbuster "Avengers: Doomsday" will debut in cinemas on 18 December 2026. The film is the first half of a two‑part finale to the MCU’s Multiverse Saga and will unite characters from the main MCU, the X‑Men, the Fantastic Four and other Marvel universes.

Robert Downey Jr. returns to the franchise, not as Tony Stark but as the new antagonist Doctor Doom. Concept art released by former visual‑development director Andy Park shows Downey Jr.’s Doctor Doom mask and confirms the appearance of X‑Men (Magneto, Professor X, Mystique, etc.) and Fantastic Four members. The Russo brothers will direct, and they have said the film will explain the visual similarity between Doom and Stark.

The runtime is listed at 165 minutes (2 hours 45 minutes). Despite occasional rumors of editing difficulties, Marvel says the production remains on schedule for its December release worldwide.