Tom (Steve Martin) and Kate Baker (Bonnie Hunt) have compromised their careers to raise 12 children. Tom coaches a high-school football team, while Kate has retired from journalism to raise the family. Things change when Tom is offered a college coaching job in a new city at the same time a publisher buys Kate's parenting memoir. After moving, Kate goes on a book tour, leaving Tom in charge of the children, who -- already unhappy about relocating -- plunge the household into chaos.