The movie, written and directed by James Gunn, stars Idris Elba, Margot Robbie, John Cena, Jai Courtney, Joel Kinnaman, Nathan Fillion, Michael Rooker, Pete Davidson, Sylvester Stallone, Storm Reid, Taika Waititi, Sean Gunn, David Dastmalchian, Peter Capaldi, and Viola Davis.