Siddharth said the idea of "War" came to him post Bang Bang! when he was travelling. He picked up a habit which he didn't have earlier: reading books. "During 2015-2016, I travelled a lot and was intrigued by the genre of spy thrillers and I picked up a lot of books of top novelists. The idea of the film came from there. It opened my imagination to conflicts, characterisation, drama and plot points.