Costume designers Sandy Powell and Christopher Peterson had the monumental responsibility of dressing Al Pacino and Robert De Niro "like regular folks, people who don't want to be photographed" - not just for one period of time but for over 5 decades. Director Scorsese's instruction was that the clothes - in particular the suits - had to look "natural and lived-in", apart from being time-appropriate, of course. You can suit up according to the Oscar-nominated duo's vision with British menswear label Paul Smith, who always brings a little quirk to its classic tailoring.