It is about the rise and fall of Henry Hill (Ray Liotta), a half-Irish, half-Sicilian boy living in New York and he states in the introduction of the film that "As far back as I can remember, I always wanted to be a gangster."Hence when he gets the chance he begins hanging around with the local mobsters, this is early in his school years. They soon have him running errands and doing odd jobs.
Since this is what he always wanted it doesn't take him long to move up in the world, after a few short years he gets pinched by the police while doing a small job. He is about to plead guilty until the mob lawyer walks into the court room, this event distinguishes himself as a "stand-up guy" as he was about to choose jail time over ratting on his friends.
Now he is a part of the family, and soon rises up through the ranks. That is as far as a "half-Sicilian" can go. Only a full Sicilian can become a "made" guy, and hence untouchable within the mob. This limits the opportunities for him, and after a while he goes behind his boss and starts dealing in drugs. The money is just too good to refuse.
Going against the boss is never a good idea, so soon he has both the feds and his boss after him. This leaves only one option if he is to stay alive, jail time isn't the issue. So he decides to break the golden rule of "never rat on your friends" and become a witness for the feds.
