 Initial discussions took place in 2008 between Tom Cruise and Noyce about Cruise playing Edwin A. Salt . These discussions were ongoing for more than a year between the pair and their representatives . It was finally decided that Cruise was unable to commit to the script , because he feared that the character was too close to his Mission : Impossible character Ethan Hunt . Cruise decided to work on Knight and Day instead . The filmmakers tried to differentiate the character from Hunt , but eventually came to accept they were too similar and decided not to change the characteristics of Salt . Noyce said " But , you know , he had a valid point . It was kind of returning to an offshoot of a character that he ’ d already played . It ’ s like playing the brother , or the cousin , of somebody that you played in another movie " . 
