Jeremy on a hunting trip and pranks them, resulting in Jeremy getting shot in the buttocks. While Jeremy recovers, John and Claire go on a bike ride to a secluded beach. Claire finally admits she is not sure how she feels about Sack and ends up kissing John passionately. Meanwhile, Gloria tends to Jeremy's wounds and reveals to him that she is not a virgin as she initially told him. Jeremy realizes that he himself has been played and that he may be in love with Gloria. While John is confessing his attraction to Claire, they are interrupted by Jeremy being chased out of the house. Sack, who had been investigating them, reveals John and Jeremy's real identities to the family. Betrayed, Claire turns on John, and the Secretary tells them to leave. Over the following months, John attempts to reach Claire, but she refuses to see him. Expecting Jeremy to aid him, he attempts to sneak into her and Sack's engagement party but is caught and beaten by Sack. Confronting Jeremy about abandoning him, he learns that Jeremy has secretly continued his relationship with Gloria. Betrayed and brokenhearted, John spirals into depression, crashes weddings alone and becomes nihilistic and suicidal. Meanwhile, as Claire and Sack plan their wedding, Claire's doubts about her future with Sack grow. Jeremy proposes to Gloria and tries to ask John to be his best man, but John turns him away. John visits Jeremy's former wedding crashing mentor, Chazz Reinhold, who convinces a reluctant John to crash a funeral with him. At the funeral, John reconsiders his belief in love and marriage after seeing the grieving widow. He rushes to Jeremy's wedding and joins the wedding mid-ceremony, to Jeremy's delight. Claire is upset by his appearance, prompting John to express regret for his past behavior and profess his love for her in front of the congregation. Sack interrupts, but Claire finally tells him that she cannot marry him. Sack tries to attack John, but Jeremy intervenes and knocks him out, and John and Claire kiss. After the wedding, the two couples drive away from the ceremony and discuss crashing another wedding together. Cast Owen Wilson as John Beckwith Vince Vaughn as Jeremy Grey Christopher Walken as U.S. Secretary William Cleary Rachel McAdams as Claire Cleary, William & Kathleen's daughter and John's love interest Isla Fisher as Gloria Cleary, William & Kathleen's daughter and Jeremy's love