When Frank Beardsley (Dennis Quaid), a widower of 8 children runs into his high school sweetheart, Helen North (Rene Russo), it's as if thirty years never passed! Helen, also a widow with ten kids of her own that include the six she and her husband adopted, feels the attraction as well. It's no wonder they rush into marriage without telling their kids. True love can conquer all—right? Unfortunately for Frank and Helen, the families don't mesh quite as easily as the newlyweds had hoped. They probably should have seen the culture clash coming: the disciplined Beardsleys run things by the book, for the energetic and vivacious Norths, there is no book. Helen's kids aren't pleased about moving and sharing rooms with a bunch of uptight strangers. Frank's children have nothing in common with the Norths. Since both sets of kids aren't happy, they devise a plan to undermine the marriage and team up to plot the breakup. East meets west as the two families finds a way to work together—in order to separate. Just when it appears that the kids have succeeded, they realize they like each other despite their differences—they don't want their families to split up! Can they save Frank and Helen's marriage after they so brilliantly split them up? It's up to Frank and Helen!