Kevin Costner stars as Roy Tin Cup McAvoy, an ex-golf pro who now lives in a Winnebago and runs a driving range in the middle of nowhere. Stuck in his sloppy bachelor lifestyle and hiding from the IRS, he has failed to make anything of the opportunities that have come up in his past. One day, Molly Griswold (Rene Russo) arrives at the range seeking golf lessons. She is a psychologist stuck in an unhappy relationship whose problems often mirror Roys struggle with life and golf. Always aware when people are lying to themselves, but unable to tell when people are lying to her, she resists Roys attempt to get her to leave her boyfriend who just happens to be Roys long-time nemesis; unpleasant PGA superstar David Simms (Don Johnson).
Roy doesnt really seem to understand women, and his advances seem at first to be getting him nowhere his obsession with Molly distracts him from his game, and he tries everything he can think of to get his golf swing back. As he tries to find ways to impress her, Molly inspires Roy to make an effort at regaining his self-respect and he decides to try to qualify for the US open, taking his close friend Romeo Posar (Cheech Marin) to caddy for him. Along the way he learns something of the meaning of life, discovers what is really important, and puts his game into perspective.
Witty and well put-together, Tin Cup is an entertaining if typical Costner romantic sports comedy with plenty of energy. The plot is no great surprise at times, although it works its way to a generally surprising climax and satisfying non-Hollywood ending where Roy doesnt get things all his own way. The strong cast work well together, although it would have been nice to see a bit more chemistry between Costner and Russo as the romantic leads. The conflict between Costner and Johnson however is top notch and the two clearly enjoy working together. The golf is authentic throughout, helped by the participation of genuine commentators and pro golfers, reinforcing Costners reputation for making realistic sports-related films.