Sandler portrays a 30-something loser living in South Manhattan, who has been milking a minor foot injury to the tune of a $200,000 court settlement and whose life, consequently, consists of miniscule employment, a general lack of direction, and a girlfriend who's ready to move on to an older man with a "5-year plan". When a little boy suddenly shows up on his doorstep (the hitherto unknown son of a friend of his), Sandler decides to temporarily take him under his wing in the hopes of winning his girlfriend back. Thus, a man with almost no resources of adult maturity attempts to instill skewed life lessons into a willing, highly impressionable young mind. This leads to Sandler's teaching the boy to indulge in predictable, but surprisingly timid, antisocial behavior such as urinating on public buildings, staying up late, tripping unsuspecting rollerbladers etc. The film is not always at its peak of creative freshness at such times, but Sandler's lowkey cynicism provides some humor.
As Sandler grows to care for his tot and the inevitable forces array themselves against him to take the child away, the film veers off in the direction of sappiness and maudlin tearjerking. One may be moved at times, but one also craves the satirical sharpness and bite that a more courageous screenplay might have provided.
The movie does display an enlightened view of gays (though Hollywood has yet to get past the point where gay characters can do more than merely twinkle at each other), but it loses points for its rather nasty tone towards old people. Still, any film designed to send Dr. Laura into spasms of psychoanalytical outrage should be respected and honored.
Overall, "Big Daddy" is a movie that, if it had taken more audacious pathways, might have been a firstrate comedy. As it is, it provides numerous chuckles and a cuddly warm feeling - and that, given the state of much of big screen comedy these days, is about all we dare allow ourselves to expect.