 Eon believed that they had relied too heavily on CGI effects in the more recent films , particularly Die Another Day , and were keen to accomplish the stunts in Casino Royale " the old fashioned way " . In keeping with this drive for more realism , screenwriters Purvis , Wade and Haggis wanted the script to follow as closely as possible to the original 1953 novel , keeping Fleming 's darker storyline and characterisation of Bond . 
