The plot revolves around college friends who have reunited in London for the marriage of their friend, Dr. Mary Lewis. Megan discovers that her best friend, Laurie, has been fighting breast cancer for the past seven months. Laurie has kept her illness a secret from Megan due to the fact that Megan recently lost her lover, Danielle, to inflammatory breast cancer.
Despite Laurie's positive attitude and efforts to live a long, fulfilling life, her self-esteem and image have been shattered by the mastectomy and her ex-boyfriend's insensitivity. Complicating Laurie's weekend is the thought of seeing Gail, who still believes that Laurie stole her boyfriend in college. Mary, Laurie and Megan begin their celebration at a local pub. Gail arrives, late as usual, and begins to antagonize Laurie until she storms out. Megan chases after Laurie while Mary scolds Gail for ruining her party.
To further complicate things, Mary's younger brother, Peter, shows up a few days early to woo Laurie and see if his long standing unrequited love can finally be returned. Despite his charm, Laurie does not feel ready for any sort of commitment.
When Megan realizes that Stuart destroyed Laurie's self-esteem by walking out after the surgery she tries to comfort Laurie with everything from tough love to wisecracks, and in doing so rekindles an unrequited passion. Alone in the garden of Mary's fiancees' country home, frustrated by her inability to comfort Laurie, Megan kisses her. Laurie runs off leaving Megan feeling incredibly stupid.
Laurie confronts Megan about the kiss and Megan tries to explain that she tried every other way she knew of to make Laurie understand that she is still beautiful and desirable. Laurie reminds Megan that she made it clear in college that their love could only be platonic. Megan acknowledges that despite the fact she knows that, she also knows how Laurie feels after the surgery. Faced with Laurie's news, Megan breaks down over Danielle's untimely death and expresses her fear of losing her best friend, too.
Gail starts to antagonize Laurie at Mary's bachelorette party, and Laurie tells her about the cancer and Stuart's insensitivity. Angry that she is always the last to know, Gail tells Laurie that she does not feel sorry for her. Only after Laurie leaves does Gail realize the level of her insensitivity and begins to question Mary and Megan about the cancer. In an attempt to make peace with Laurie, Gail tries to show her genuine concern for her old friend. When they make amends, Gail asks to see the scar.
Aided by Megan, Peter tries again to woo Laurie at the reception. When Laurie agrees to dance with him, Peter confesses his feelings for her. Laurie tries to push him away, but he persists until Laurie blurts out that she has had a mastectomy. Shocked Peter doesn't know what to say and Laurie tells him to leave. Peter refuses, telling her that he is in love with her regardless of what has happened. Still reluctant to trust men, Laurie finally agrees to give him a chance.