Robert Downey Jr. recently appeared on ‘The Late Show with David Letterman,’ to promote ‘Avengers: Age of Ultron. During the interview, RDJ spoke briefly on ‘Captain America: Civil War’ and explained the concept of the film to a very confused Letterman.

“There was a strain of comics where Captain America and Iron Man, they went on different sides and they fought each other,” Downey says.

“Do you win? You must win,” Letterman replied.

Letterman asked if Spider-Man was going to make an appearance in the film, RDJ replied, “He may well be… Yeah, I hear that they’re looking to cast a new Spider-Man.”

http://www.youtube.com/watch?v=aL81IVOqWNo

Directed by Joe & Anthony Russo. Stars: Chris Evans as Steve Rogers/Captain America, Robert Downey Jr. as Tony Stark/Iron Man, Chadwick Boseman as T’Challa/Black Panther, Frank Grillo as Brock Rumlow/Crossbones, Anthony Mackie as Sam Wilson/Falcon, & Daniel Brühl. Expected to return: Sebastian Stan as Bucky Barnes/Winter Soldier, Scarlett Johansson as Natasha Romanoff/Black Widow, and Samuel L. Jackson as Nick Fury. Rumored: Jeremy Renner as Clint Barton/Hawkeye.

‘Captain America: Civil War’ opens in theaters May 6, 2016.