Brennan Huff (Ferrell) is a sporadically employed thirty-nine-year-old who lives with his mother, Nancy (Mary Steenburgen, Melvin and Howard). Dale Doback (Reilly) is a terminally unemployed forty-year-old who lives with his father, Robert (Richard Jenkins, Six Feet Under). When Robert and Nancy get married and move in together, Brennan and Dale are forced to live with each other as stepbrothers. Their narcissism and downright aggressive laziness eventually tear the family apart--their parents eventually divorce due to Brennan and Dale's wild antics, specifically the destruction of Robert's sailboat while shooting a "music" video. Eventually, these two middle-aged, immature, overgrown boys begin to grow-up and work to bring their parents back together.