The Italian gangster film Gomorrah from 2008 is too awesome to miss. Black Mass (2015) with Johnny Depp as Whitey Bulger never got the love it deserved. Really terrifying. Any gangster movie directed by Jean-Pieere Melville, like Le Samouraï, Bob Le Flambuer, or The Red Circle is better than almost anything out there. Drunken Angel (1948) by the master Kurosawa deserves a mention.

Those Mesrine movies are off the hook. That was a real criminal right there.