These self-appointed dispensers of justice are usually driven by an intense internal rage, seeking to exact revenge on those who've crossed them or come to the aid of the weak and defenceless.
Though America has traditionally been the home for the movie vigilante, this week sees London play host to blood-spattered black comedy May I Kill U? The film stars Kevin Bishop as a bicycle-riding police officer who wages war on against crooks in the capital - "a psychopath on the cycle path".
To mark the release of May I Kill U?, Digital Spy takes a look at 15 of film's most memorable vigilantes below...
May I Kill U? is showing in UK cinemas from today.