 After Warner Bros. officially became involved , the studio claimed that because Paramount had not fully reimbursed Universal for its development costs , Paramount had no legal claim over the film rights . Therefore , it would not be entitled to co @-@ finance the film with Warner Bros. After negotiations between the studios , they agreed that Paramount would own 25 % of the film and would distribute it outside North America . Impressed with Zack Snyder 's work on the film 300 , an adaptation of Frank Miller 's comic book of the same name , Warner Bros. approached him to direct an adaptation of Watchmen . After spending a couple of weeks deciding whether he wanted to direct the film or not , Warner Bros. officially announced Snyder ’ s hiring on June 23 , 2006 , with Alex Tse attached to write the script . Drawing from " the best elements " from two of Hayter ’ s drafts , Tse ’ s script returned to the original Cold War setting of the Watchmen comic . Warner Bros. was open to keeping the 1980s setting , although less so to the R @-@ rating that Snyder wanted ; Snyder also decided to add a title montage sequence to introduce the audience to the alternate history of the United States that the film presented . Snyder kept the ending from one of Hayter 's drafts , which simplified details of the conspiracy within the story , because he felt it would allow more screen time to explore characters ' backstories . 
