 Mayank and Rohit Shetty had originally planned to team up for a remake of the 1982 film , Angoor . After the 2011 blockbuster Singham , Shetty had begun writing the script of the film but left it half @-@ finished . The script of Chennai Express was ready for Shah Rukh Khan as a back @-@ up , because of the difficulty of obtaining the actor 's filming dates . Upon reading the script , Khan liked the idea and agreed to star in it before the Angoor remake , causing Angoor 's remake to be postponed . Shetty said the film is " a hard @-@ core commercial film with a romantic angle . The story is about this man 's travel from Mumbai to Rameshwaram and what happens during the journey . " About 68 minutes of footage were enhanced with CGI by Reliance MediaWorks . 
