dredd
I have very, very vague memories of Sylvester Stallone as the perpetually grimacing Judge Dredd (from the film adaptation that strayed from the source material and became a commercial and critical disappointment), and I haven't read any of the 2000 AD titles where the character appears, but it doesn't matter: Dredd is that rare kind of science fiction film that immerses the audience in a fleshed-out world without resorting to infodumps and endless exposition.
Judge Dredd (Karl Urban) is a member of a group of urban cops called "Judges", who has the combined powers of a policeman, judge, jury, and instant executioner. They maintain order in the American wasteland of Mega City One, which runs from Boston to Washington DC. During a routine day, Dredd rides out with a rookie named Anderson (Olivia Thirlby) to a 200-storey building now controlled by drug lord Ma-Ma (Lena Headey) after the Ma-Ma gang wins in a bloody turf war.
This is not an origin story. It is a routine day on the job of a policeman in a world so bleak and ruined that the Judges become a necessity. This is the world. This is the crime. These are the Judges. This is what they must do. It is a straightforward action film that only hints at the past lives and tragedies of Anderson and Ma-Ma. Of Judge Dredd's past we will know nothing at all. We don't know if his thirst for justice is propelled by a personal experience. In this film at least, he is more of a symbol than an actual character. Not once does he take off his helmet.
The script is by Alex Garland, one of my favorite screenwriters and novelists. I absolutely loved the look and atmosphere of the film. I would watch Dredd again.