 Chicago resident Chester "Chet" Ripley, his wife Connie , and their two sons Buck and Benny are on vacation at a lake in Minnesota, where they have rented a two-story cabin. Not long into the vacation, the unexpected happens -- Connie s sister Kate, Kate s know-it-all husband Roman Craig, and Kate and Roman s twin daughters Mara and Cara crash the vacation. Roman proceeds to get on Chet s nerves -- so much that Chet is ready and willing to pack up and go home, even as teenager Buck tries to romance a local girl named Cammie. It turns out that the reason why Roman, Kate, and the twins crashed the vacation is because the Craigs are broke, and Roman was planning to borrow $25,000 from Chet.