Third-Person Omniscient

The movie opens with a monologue by Frank Costello, but it isn't long before it takes us into the perspective of different characters like Colin Sullivan and Billy Costigan. A big part of the fun in this movie is knowing a ton of stuff that the characters don't—and wondering which characters are going to figure everything out. Some of the most enjoyable scenes are those in which Billy and Colin are right on the verge of finding out each other's identities.

It's not until the very end of the movie that everyone actually learns everything, but by that point—spoiler alert!—all the main characters are dead, anyway. But—oh, well. At least Sergeant Dignam gets to walk away from the whole thing without a scratch on him.