While in his honeymoon in a paradisaical beach, the conservative risk analyst of an insurance company Reuben Feffer (Ben Stiller) finds his wife Lisa Kramer having sex with her scuba instructor Claude in his boat. Reuben immediately returns to New York and his friend Sandy Lyle (Philip Seymour Hoffman) invites him to go to a party. There he meets his former high school friend Polly Prince (Jennifer Aniston), who is a very independent woman that lives in the edge with her blind ferret in a cozy but simple apartment. Although having very different behaviours, they date and feel a great attraction for each other. When Lisa returns, Reuben has to decide if he wants to live his life in the suburb with his unfaithful wife, or have a risky relationship with Polly.