4. Raging Bull
Scorsese has made some fantastic biopics but this is easily his best and possibly his best movie in general. Raging Bull focuses on the character of Jake LaMotta who is one of the most challenging protagonists in the history of film. Scorsese presents LaMotta as a broken man but never as someone that the audience is meant to hate or pity which makes him that much more polarizing since it's never made clear just how we're supposed to feel about him. Some people find the film to be impossible to watch because nothing is ever defined but this actually makes it better, especially as a biopic. Scorsese forgoes all of the traditional rules of the standard biographical movie and just gives viewers an honest and realistic portrayal of a man who has faults and issues just like everyone else. This allows viewers to make up their own mind about LaMotta instead of having the filmmakers tell them how they should think.