When Avengers: Endgame premiered in theaters, it was supposed to be just that: the endgame. Characters were sacrificed, others were revived, and the next chapter of the Marvel Cinematic Universe was established. The last time we saw Steve Rogers in Avengers: Endgame, he had traveled back in time and aged into an old man. Marvel StudiosLeaker Daniel Richtman claims to have insider knowledge of the first of four Avengers: Doomsday trailers. Avengers: Doomsday premieres in theaters on December 18, 2026.