Filmmaker Rajkumar Hirani, who worked with Aamir Khan in 'PK' and '3 Idiots', revealed the actor writes down all his dialogues himself after reading the script. "Aamir loves to listen to the script, work on it and put his questions forward," he added. Hirani further stated that actor Arshad Warsi, meanwhile, operates oppositely as he thrives on spontaneity and improvisation.