According to Wikipedia, Beau Geste is the only movie that features as many as four Academy Award winners for Best Actor
in a Leading Role (Gary Cooper, Ray Milland, Susan Hayward, Broderick Crawford) prior to any of the actors receiving the Best Actor Award.
Fast Times at Ridgemont High has three (Nicholas Cage, Forrest Whitaker, and Sean Penn).
What movie features the **most **Academy Award Winners who had received their Oscar(s) before the film was made?
So far, I’m thinking Grumpier Old Men (Jack Lemmon, Walter Matthau, and Sophia Loren) and Steel Magnolias (Sally Field, Shirley McLaine, and Olympia Dukakis) are the winners…Do I hear four?
Nine (2009) has six: Daniel Day-Lewis (1989, 2007), Judi Dench (1998), Marion Cotillard (2007), Penelope Cruz (2008), Nicole Kidman (2002), and Sophia Loren (1960).
The Dark Knight Rises (2012) has four: (and five total with Anne Hathaway):
Christian Bale (2010), Morgan Freeman (2004), Michael Caine, and Marion Cotillard.
Kenneth Branagh’s Hamlet: Charlton Heston, John Mills, John Gielgud, Jack Lemmon, Julie Christie, Judi Dench, Kate Winslet, Robin Williams, and Richard Attenborough (Director)
9 Former Oscar Winners: Cher, Louise Fletcher, Whoopi Goldberg, Joel Grey, Anjelica Huston, Jack Lemmon, Marlee Matlin, Sydney Pollack, Rod Steiger
4 Future Oscar Winners: James Coburn, Tim Robbins, Julia Roberts, Susan Sarandon
Interestingly, The Muppet Movie has 6, but only one of those 6 won for acting: Edgar Bergen, Mel Brooks, Bob Hope, Cloris Leachman, Orson Welles, Paul Williams
The documentary Looking for Richard has 7: F. Murray Abraham, John Gielgud, Kevin Kline, Al Pacino, Estelle Parsons, Vanessa Redgrave & Kevin Spacey (all interviews or performance, no archival footage)
The Oscar was a film with 7 as well: Ed Begley, Ernest Borgnine, Walter Brennan, Joan Crawford, James Dunn, Edith Head, Bob Hope, and Frank Sinatra
Films with 5 former winners: Around the World in 80 Days* (1956) - Charles Coburn, Ronald Colman, Noel Coward, Victor McLaglen, Frank Sinatra How the West Was Won (1963) - Walter Brennan, Karl Malden, Gregory Peck, Jimmy Stewart, Spencer Tracy
*also featured 5 future winners (John Gielgud, Buster Keaton, Shirley MacLaine, John Mills, David Niven)