In 1967, United Artists paid more than $2.25 million for rights to the show, the second most ever paid, behind the $5.5 million that Warner Bros. paid for the rights to "My Fair Lady". In addition to the initial outlay, UA agreed to pay 25% of the gross if the gross exceeded 2.5 times the negative cost plus $0.5 million for album sales. According to both associate producer Saul Chaplin (in his memoir "The Golden Age of Movie Musicals and Me") and Dale Wasserman (in his memoir "The Impossible Musical"), the film had a troubled production history. Originally, Wasserman, composer Mitch Leigh – serving as associate producer – and Albert Marre, who had directed the original show but had never before directed a film, were hired to make the motion picture, and original cast stars Richard Kiley and Joan Diener were screen tested in anticipation of the two actors repeating their stage roles. Because of Marre's inexperience with moviemaking, however, he (according to Wasserman) used up part of the film's budget on screen tests, which angered the UA executives. Marre was fired, and as a result Wasserman, Leigh, Kiley and Diener, who was married to Marre, also left the project. British director Peter Glenville was then brought in (it was he who cast Peter O'Toole as Cervantes and Quixote), but was in turn also fired when it was learned that he planned to eliminate most of the songs. It was then that Arthur Hiller and Saul Chaplin joined the project. Hiller re-hired Wasserman to adapt his own stage libretto, although, according to Wasserman, the film's new opening sequence, showing the actual arrest of Cervantes "before" he enters the prison, was not by him. Writer John Hopkins, who most likely wrote the scene Wasserman refers to, had been brought in by Glenville, and had left when Glenville was fired. However, it has never been made clear whether it was Glenville or Hiller who cast non-singing actors Sophia Loren, Harry Andrews, and Rosalie Crutchley in the film, it might have been Glenville, since he had tried to eliminate the songs and envisioned the film as a non-musical. Glenville had also previously worked with arranger/conductor Laurence Rosenthal.