奈尔斯（安迪·萨姆伯格 Andy Samberg 饰）和女友的感情之路早已经走到了尽头，可即便如此，他还是勉强跟着她去参加了一场婚礼。婚礼现场，谁也不认识的奈尔斯百无聊赖，一个名为萨拉（克丽斯汀·米里奥蒂 Cristin Milioti 饰）的放荡不羁的女孩吸引了奈尔斯的注意。 　　萨拉是新娘的姐姐，实际上，她和新郎长期保持着肉体关系，就连新婚前一晚，她都是在新郎的床上度过的！这样一个令全家人都感到头疼的姑娘，在奈尔斯的眼中却显得格外有吸引力，在同女友分手后，奈尔斯和萨拉渐渐走到了一起。萨拉泼辣的个性给奈尔斯的生活带来了惊喜，却也制造了种种麻烦，当奈尔斯发现自己真的深深地爱上了萨拉时，后者却不告而别。While stuck at a wedding in Palm Springs, Nyles (Andy Samberg) meets Sarah (Cristin Milioti), the maid of honor and family black sheep. After he rescues her from a disastrous toast, Sarah becomes drawn to Nyles and his offbeat nihilism. But when their impromptu tryst is thwarted by a surreal interruption, Sarah must join Nyles in embracing the idea that nothing really matters, and they begin wreaking spirited havoc on the wedding celebration.