Hong Kong action cinema
Stahelski and Leitch's approach to fight scenes drew upon their admiration for anime and martial arts films. The film used fight choreographers and gun fu techniques from Hong Kong action cinema. The film also pays homage to works such as John Woo's "The Killer", Jean-Pierre Melville's "Le Cercle Rouge" and "Le Samouraï", John Boorman's "Point Blank", and the Spaghetti Western films.