It's vacation time for outdoorsy Chicago man Chet Ripley (John Candy), along with his wife, Connie (Stephanie Faracy), and their two kids, Buck (Chris Young) and Ben (Ian Giatti). But a serene weekend of fishing at a Wisconsin lakeside cabin gets crashed by Connie's obnoxious brother-in-law, Roman Craig (Dan Aykroyd), his wife, Kate (Annette Bening), and the couple's two daughters. As the excursion wears on, the Ripleys find themselves at odds with the stuffy Craig family.