Only time Rishi Kapoor and Irfan Khan worked in a film.They both passed away in a days difference.Irfan Khan on 29 April 29 2020 and Rishi Kapoor on 30 April 2020 both due to cancer.
Rishi Kapoor's character which is based on Dawood Ibrahim is shown speaking Marathi in many scenes as Dawood Ibrahim was a Konkani Muslim from Ratnagiri he spoke Marathi.
Anil kapoor was the first choice to play the role of 'ashwini'
Abhay Deol was signed but opted out. Irrfan replaced him.
D-Day was filmed in well known bungalow scheme named Sentossa Greenland and other areas of Ahmedabad, Gujarat.