Here's an original idea: Let's get a well-known comedian to dress up in women's clothes and make jokes in a movie. You've seen it before, you say? Too true. Mrs. Doubtfire and Tootsie -- not to mention Uncle Miltie and, of course, Some Like It Hot -- have gone this route, quite successfully. So, it seems only natural that Martin Lawrence would try to cash in on some of the seeming popularity of the gimmick in Big Momma's House. Rated PG-13, this film isn't nearly as rough as tumble as you'd expect from Lawrence. In fact, Martin's usual crass posturing has been replaced by, you could say, "ass posturing" (Big Momma's backside is huge).

This is a perfect example of a movie that could have been killed by its own "high concept". The idea here so overshadows the story that plot goes out the window and the gimmicks rule the film. But then, you don't really expect much more when you walk into this movie. Here, the deal is simple: Dress up funny man Lawrence as a fat lady and let her/him sing.

Lawrence conveniently happens to be "master of disguise" FBI agent Marcus who is forced to go undercover as Southern grandma Big Momma in order to get close to the woman's granddaughter Sherry (Nia Long), a sweetheart of a girl who defines the word "hottie". Poor Sherry has some nasty ties to murderer Lester (Terrence Howard), who has just escaped from prison and is eager to get hold of the $2 million that the FBI thinks he stashed with Sherry. When Sherry sees Lester's face on the news, she goes on the run with her son Trent (Jascha Washington) and ends up desperate at Big Momma's doorstep.

As stated, because the film starts as one big gimmick, it tends to continue on this route, showing Lawrence's Big Momma in a number of predictable Southern scenarios -- cooking in the kitchen with a pound of lard, playing basketball with the homeboys and testifying at church. Through it all, his nervous sidekick partner John (Paul Giamatti) sweats over Malcolm's every move. The biggest problem, of course, is Malcolm's sex drive, which goes into overdrive when he sees Sherry in numerous compromising situations. When he does accidentally blow his cover, he rallies back by doffing his fat suit and pretending to be Big Momma's handyman. Translation: They needed to get the love story in there somehow.

Lawrence does an amusing job playing a big-hipped, Southern granny, even if some of the stunts he pulls are predictable. After all, you know that every time this guy hugs Sherry, he's going to get a bit, well, excited. And this, of course, pops up -- pardon the pun -- more than once. That, in fact, is about the level of all the humor. Fat, sex, fat, sex. Surprisingly, they get a lot of mileage out of both. Lest you be completely turned off by the simplicity of it all, you can rest assured that there is also some real heart -- and soul -- in this flick. There are some great moments between Malcolm (as both Big Momma and the handyman) and Sherry's son Trent as well as a karate scene that is definitely worth seeing.

No Oscar nominations are going to go to this film and no one is going to run to the theater for multiple viewings. It is actually the sort of movie that's custom-made for video -- inane and harmless, often funny, sometimes touching. It certainly stumbles along the way, but, hey, when you're at home on a Saturday afternoon coping with a week of stress, Big Momma may have just the right medicine.