But exactly what the plot of that movie actually is is anybody's guess. We know that it will include the return of Robert Downey Jr., now playing Doctor Doom, but an intriguing theory suggests how a potentially returning Chris Evans and Captain America may factor in, and how it will actually all tie into Avengers: Endgame.

Avengers: Doomsday has taken an intriguing turn with Chris Evans joining Robert Downey Jr. in the cast. While Downey Jr.’s role as Doctor Doom was revealed at San Diego Comic-Con, Evans’ character remains a mystery,

A major player in the Marvel Cinematic Universe's Multiverse Saga won't be appearing in Avengers: Doomsday, although they will return for Secret Wars.

Benedict Cumberbatch reveals that Doctor Strange won't be in 'Avengers: Doomsday.' Also, he was just as surprised as anyone by Robert Downey's MCU return.

Luckily, Benedict Cumberbatch confirmed his MCU return, and revealed which Avengers movies to expect Doctor Strange. Fans who spent years watching the Marvel movies in order know that entire phases of the shared universe come to a head with the Avengers flicks.