Heres the first trailer for Marvel Studios biggest movie yet, "Avengers: Infinity War."

In the upcoming superhero movie, the Avengers join forces with the Guardians of the Galaxy to confront Thanos, who is trying to collect the Infinity Stones.

If you thought that the cast of "Captain America," with its two opposing sides of superheroes was huge, "Avengers: Infinity War" is about to deliver at least twice the cast.

"Avengers: Infinity War" is the beginning of the end for the first major story arc of the Marvel Cinematic Universe and features almost every main character from the Marvel Cinematic Universe to date.

"Avengers: Infinity War " debuts May 4 and is directed by Anthony and Joe Russo, who helmed "Captain America: Civil War" and "Captain  America: The Winter Soldier."

"Avengers 4" follows on May 3, 2019.