The movie industry is a fickle business and scripts are often touted around a number of people before a director and cast attach themselves. Over the years a number of classic and beloved movies have been made by second or even third choice directors and actors. We can only wonder how these films would have turned out had they been made by the studio´s first choice.
Dustin Hoffman was the first choice to play Deckard in Bladerunner and apparently a host of other actors were considered before Harrison Ford got the part. According to writer Philip K. Dick Martin Scorcese was interested in directing but never optioned the novel.
Kubrick considered both Robert De Niro and Robin Williams to play the part of Jack in The Shining before settling on Jack Nicholson. Stephen King, author of the book on which the film is based, wanted Michael Moriarty or Jon Voight for the role.
Alien was going to be directed by Walter Hill but after helping re-write the script the production was delayed and he pulled out to make way for Ridley Scott.
The central role of Andy in the hugely popular film The Shawshank Redemption was turned down by Tom Hanks and Kevin Costner before it was offered to Tim Robbins. Rob Reiner also tried to buy the rights from Frank Darabont intending to direct it himself and he planned to cast Tom Cruise in the lead role.
The Godfather was offered to Italian director Sergio Leone who turned it down and Coppola was reportedly close to being replaced a number of times as his relationship with Paramount turned sour. The studio also wanted someone other than Brando for the role of Vito Corleone and apparently Ernest Borgnine and Orson Welles were considered but Coppola insisted on Brando. Warren Beatty, Jack Nicholson and Dustin Hoffman all turned down the role of Michael Corleone and Martin Sheen also auditioned for the part before Coppola settled on the then relatively unknown Al Pacino.
Al Pacino has turned down a number of fantastic parts in his career including the role of Jimmy Conway in Goodfellas which went to Robert De Niro, he also turned down the part of Han Solo in Star Wars and Captain Willard in Apocalypse Now. The part of Willard was first turned down by Steve McQueen and shooting started with Harvey Keitel in the role before Coppola replaced him two weeks into production with Martin Sheen.
When making Pulp Fiction Tarantino wanted Michael Madsen to play the role of Vincent Vega but he turned it down to do the Kevin Costner film Wyatt Earp. Daniel Day-Lewis also reportedly wanted the part but Tarantino rejected him in favour of John Travolta.
Tom Selleck was actually cast in the role of Indiana Jones for Raiders of the Lost Ark but pulled out to continue making Magnum P.I. Apparently George Lucas resisted casting Harrison Ford in the part keen to avoid him becoming "that guy I put in all my movies", luckily Spielberg eventually persuaded him Ford was perfect for the role.
Will Smith and Nicolas Cage both turned down the part of Neo in The Matrix and it eventually went to Keanu Reeves. Sean Connery turned down the part of Morpheus which eventually went to Laurence Fishburne. Connery also turned down the role of Gandalf in the Lord of the Rings trilogy and he only got the part of James Bond in Dr. No after Cary Grant decided he was too old for the part and refused it.
Terry Gilliam turned down the chance to direct American Beauty and unbelievably Chevy Chase turned down the role that won Kevin Spacey an Oscar.
Mel Gibson turned down the role of Maximus in Gladiator, the part which won Russell Crowe an Oscar. Gibson also declined Costner´s part in Robin Hood: Prince of Thieves and he only ended up directing Braveheart after Terry Gilliam turned it down. Gilliam also rejected the chance to direct Forrest Gump and Who Framed Roger Rabbit.
Jack Lemmon turned down the role of Butch in Butch Cassidy and the Sundance Kid and Newman switched roles from Sundance to Butch when Steve McQueen was cast as Sundance. The part eventually went to Robert Redford.
Sidney Lumet was going to direct Scarface but backed out and Brian De Palma quit directing Flashdance so that he could take over.
When James Cameron was casting for The Terminator he considered O.J. Simpson and then Lance Henriksen for the role of the robotic killer and Schwarzenegger was originally offered the role of Kyle Reese, thankfully he eventually came to his senses and cast Schwarzenegger as the Terminator and Michael Biehn as Reese.
It is fun to consider how different many of your favourite films might have been with different actors or directors and it is interesting to note that for most if not all of the examples given above things probably worked out for the best.