On the newlyweds' honeymoon, the unexpected arrival of the groom’s eccentric best friend—who has lost both his job and his apartment—turns their family idyll into a drawn-out nightmare. A hospitable offer to stay for a few days quickly turns into a disaster as the uninvited guest moves into their home for good, making up ridiculous rules and destroying the romance. Constant mishaps, everyday chaos, and the friend’s shameless meddling in the couple’s private life begin to rapidly tear their marriage apart. Now the young wife must wage a quiet war against the childish freeloader to make her husband get his priorities straight and save their future together.