Big Daddy is a comedy film starring Adam Sandler. Sandler plays Sonny Koufax, a lazy man-child who adopts a young boy to impress his girlfriend. As Sonny learns to take care of the child, he also grows up and becomes a responsible adult. The film explores themes of fatherhood, maturity, and the importance of family, while still delivering plenty of laughs and Sandler's unique brand of humor.