The Gambler
I'm not going to lose it. I'm going to gamble it.
That is what the gamblers usually say. None is going to lose, everyone's going to win and only win. That is a common delusion. The movie is based on this phrase.
There is a college professor Axel Freed (James Caan), who is a convinced gambler. He cannot control his gambling nature anymore. He likes a beautiful lady named Billie. And everyone around likes him too, they simply do not know his true personality.

He bets on basketball games. And gradually he turns out to be in large debt. He takes some kind of his heritage left by the mother to pay out the debt. Then he takes his girlfriend to a casino and makes a small fortune but then he loses even more in a basketball games.
A Glutton for Punishment
Then he finds a "perfect" scapegoat that is his girlfriend. Then he wants to ask the money from his grandfather, who really loves him. But once the granddad learns the real situation he has nothing but disgust. And of course he doesn't give him any cash.
Then he starts thinking faster and more sophisticated, as the pay day is coming. He decides to bribe one student, who is a basketball star. The guy is to shave the points, which is not legal at all. He corrupts the guys morality.
But not everything human is erased from this man's brain. He realizes what he has done and then, maybe in order to redeem his acts, he gets into a fight with a dangerous guy who kicks his butt severely. And he gets a reminder of his dirty deeds forever.
The movie was shot during the time, when the main character and in reality James Caan was undergoing his struggle with the cocaine addiction. Apparently he won the struggle as he is still alive. Gambling addiction is an important and painful part of many people's lives.