Just like how Avengers: Infinity War and Avengers: Endgamewerereleased in back-to-back Aprils in 2018 and 2019, Marvel is looking at another one-two Avengers punch this December and next. Avengers: Doomsday is all set to premiere in theaters on Dec. 18, and Avengers: Secret Wars is slated for Dec. 17, 2027.