When Lizzie's doting father offers her the perfect destination wedding, she's deliriously happy. That is, until her "Man of Honor," Marshall, decides that his "plus one" should be his ex, Marie. Now, she has to face this unexpected disruption to her perfectly planned day. It will take the best efforts of her fiancé, Luke, and both their families to keep Lizzie focused on the wedding and from losing her mind as she tries to deal with this ex from hell.