Gwen Cummings (Sandra Bullock) is an alcoholic who spends her nights in a drunken haze with her boyfriend, Jasper (Dominic West). She ruins her sister (Elizabeth Perkins) Lily's wedding by showing up late and disheveled, delivering a drunken, rambling speech, and knocking over the wedding cake. Intoxicated, Gwen steals a limousine from the reception, tries to locate a cake store, and winds up losing control of the car and crashing into a house. She is given a choice between jail time or 28 days in a rehab center, and she chooses rehab.