亚当（罗伯特·德尼罗 Robert De Niro 饰）和艾丽（黛安·基顿 Diane Keaton 饰）曾走过20年的婚姻生涯，但如今已分手多年，亚当转而与艾丽的闺蜜贝贝（苏珊·萨兰登 Susan Sarandon 饰）在一起。原本以为生活将照例继续，怎料烦恼却随着养子亚力（本·巴恩斯 Ben Barnes 饰）的婚礼降临。亚力和女友美丝（阿曼达·塞弗里德 Amanda Seyfried 饰）两情相悦，互许婚盟，然而亚力远在哥伦比亚的生母麦当娜得知此事后，执意要来参加婚礼。为了避免尴尬，亚当和艾丽不得不貌合神离地假装恩爱，为了迎合麦当娜的清教信仰，亚力和美丝甚至想方设法请来了天主教神父，一场费尽心思的盛大婚礼终于在混乱和笑料中登场了……
本片翻拍自2006年法语喜剧《我弟弟要结婚了》。
Lewis returns to Oxford after several years absence and is reluctantly assigned by his new boss, DCS Innocent, to the murder of an Oxford mathematics student who was shot while participating in a sleep study. The key-code used to access the sleep lab was assigned to a fellow maths student, Daniel Griffin, but Daniel's math tutor has provided him with an alibi. Daniel is a maladjusted young man who will soon inherit his father's automotive empire. He is disruptive and has no respect for his uncle who now heads the company. The future of the company however rests on an impending deal with Japanese investors who insist that family unity is all important at this time. When two other murder occurs, Lewis must decipher a cryptic clue left in an old case file by his former boss, Chief Inspector Morse.
