Two that I would suggest that many haven't seen are:
Clive Owen is a struggling writer who returns to casino work, and quickly gets hooked on watching punters lose night after night. Some great scenes in this movie that are pretty accurate about long term losers, and Clive Owen is cool as a cucumber raking in money for the casino night and again. As a former casino worker and manager I can tell you MUCH of this is true for most employees.
And...
Philip Seymour Hoffman's best work bar none. Most here have probably seen it, but it centers around a bank executive who embezzles more and more to feed his gambling addiction. At one point he even gets out of debt and goes up millions, but you can guess where that goes. He even gets so desperate as to call bookies and tell them he wants every home team in the National League and every away team in the American. Minnie Driver plays a great spouse who is pushed to the brink by this psychological addiction. Great movie that really highlights the ultimate depths to which a degenerate will go...
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