[This film] stars Ben Stiller as risk-assessing Actuary Reuben Feffer and Jennifer Aniston as love interest Polly Prince. Because Feffer must know the risks inherent in many situations, he becomes inhibited by this knowledge and is unable to take any risks. While on honeymoon with his bride Lisa, she cheats on him and they split up. When he returns home, he runs into Polly Prince, a wild, risk-taking ex-classmate, and he is immediately intrigued. However, his aversion to risk taking must be overcome before he can truly be in a relationship with Prince.

Reuben Feffer is very much a stereotypical mathematician. He cites probabilities for multiple different ‘risks', including eating from the bowl of mixed nuts at a bar. He is somewhat of a stereotypical ‘nerd': he is socially awkward, a bad dancer, and has irritable bowel syndrome. His constant need to measure the risks in his life almost lead to a split with Prince when she discovers him comparing the risks between her and his ex-wife. Ultimately, he must abandon his need to measure risks to get Prince back, and he shows this by eating nuts off of a New York sidewalk.