Anurag Kashyap in his interview said that he shows men cry in this movie because he wanted to show the vulnerability of men to mainstream audience and he was tired of seeing the silent brooding and uncrying men often potrayed in Hindi cinema.
The dialogues of two characters: Robbie's Mother and Maid - are totally improvised and are different from the script.
Identical twins are shown time to time which is similar to twilight watchers in Dev D which is also Anurag kashyap film.
Identical twins dance genre is a Bfusion. "Bfusion" - a combination of Bharatnatyam, Bollywood, and hip-hop. In this movie they add a bit of Bhangara (local traditional dance type).
When the film was announced it had Dulquer Salmaan ,Ayushman Khurana and Bhumi Pednekar in the lead cast.