the credits that he wished, he wanted to be moved to the end credits with his co-stars. From the show's second season, the studio capitulated, and moved Denver's co-stars to the opening credits of the show, and also changed the theme song's lyrics to include "The Professor and Mary Ann" instead of saying "and the rest". Competitive top billing Sometimes actors can become highly competitive over the order of billing. For example: Spencer Tracy was originally cast to play the lead opposite Humphrey Bogart in The Desperate Hours (1955), but when neither actor would relinquish top billing, Tracy withdrew and was replaced by Fredric March, who took second billing to Bogart. Bogart's role in the film had earlier been played on Broadway by Paul Newman but the young actor was not considered for the movie version since Newman, viewed by studios at the time as mainly a stage and television actor only beginning his movie career, was in no position to compete with Bogart. Tracy would also later back out of costarring in the 1965 film The Cincinnati Kid when he learned he would have to take second billing behind the film's star, Steve McQueen. The role Tracy had been cast in went instead to Edward G. Robinson, whom McQueen had idolized from childhood. Whenever it was pointed out to Tracy that he routinely took top billing in his films with Katharine Hepburn, he responded, "It's a movie, not a lifeboat." Clark Gable had a top billing clause written into his MGM contract and made three major films in the 1930s with Tracy in supporting roles (San Francisco, Test Pilot, and Boom Town), but when Tracy renegotiated his contract during World War II, he had a similar clause included in his own contract, effectively ending the hugely popular Gable-Tracy team. In the opening credits of The Bridge on the River Kwai (1957), Alec Guinness, who is generally regarded as the main character in the film, receives third billing, after William Holden (who demanded top billing) and Jack Hawkins (who does not even appear until halfway through the picture). In the closing credits, Guinness is billed second, with Hawkins third. For The Man Who Shot Liberty Valance (1962), James Stewart was given top billing over John Wayne in the movie's posters and the previews (trailers) shown in cinemas and on television prior to the film's release, but in the film itself,