Watch 'Avengers' Cast Parody 'Brady Bunch' Theme on 'Fallon'

Robert Downey Jr., Scarlett Johansson, Chris Pratt, more introduce "The Marvel Bunch"

Members of the 'Avengers: Infinity War' assembled for a parody of the 'Brady Bunch' theme song on 'The Tonight Show.'

Members of the massive Avengers: Infinity War cast assembled on The Tonight Show Wednesday to create a potential new theme song for the franchise, parodying the classic Brady Bunch intro.

The bit found Robert Downey Jr. (Iron Man), Scarlett Johansson (Black Widow), Chris Hemsworth (Thor), Chris Evans (Captain America), Chris Pratt (Star Lord), Chadwick Boseman (Black Panther), Anthony Mackie (Falcon) and Benedict Cumberbatch (Dr. Strange) situated in neat blue squares and singing about their superhero exploits.

Downey Jr. started off the tune, with Johansson, Hemsworth and Evans filling in the rest of the first verse: "Here's the story/ Of a playboy genius/ Who was gearing up to form some sort of crew/ With a former Russian spy/ A god of thunder/ One fought in World War II." Pratt kicked off the second verse on the other side of the franchise, crooning, "Here's the story of a handsome Star Lord/ Like the greatest to ever walk the earth – by far," while Mackie, Cumberbatch and Boseman side-eyed him from their squares.

Anthony Russo and Joe Russo directed Avengers: Infinity War. The film opens April 27th.