What would it be like if Adam Sandler's mainstay supporting players were given a shot at writing and acting in their own Happy Madison production? That is the question answered with "Grandma's Boy," a raucous, raunchy comedy in which Allen Covert (2003's "Anger Management") takes over the sort of role Sandler (who produces) might have played eight or nine years ago. As a leading man, Covert is surprisingly winning and natural, and he is surrounded by a roster of respectable and always game co-stars who make the most of some pretty thin material.

The initial premise of 35-year-old pothead/professional video game tester Alex (Allen Covert), who is suddenly evicted from his apartment and ends up moving in with loving grandmother Lilly (Doris Roberts) and her two saucy, "Golden Girls"-inspired roommates Grace (Shirley Jones) and Bea (Shirley Knight), is ripe with comic possibilities, and earns a few very big laughs along the way. When, on the first night staying at his grandma's, he believes he is being haunted by the spirit of a recently deceased old lady who used to live in the bedroom, the payoff to this setup is one of the most hilarious movie moments in years. Likewise, when Alex's grandma and her housemates mistake his pot for tea leaves and end up drinking it, the results are lowbrow comic gold. Doris Roberts (2003's "Dickie Roberts: Former Child Star"), Shirley Knight (2002's "Divine Secrets of the Ya-Ya Sisterhood") and Shirley Jones have great fun tearing up their scenes in warm, non-stereotypical roles.

If screenwriters Covert, Barry Wernick and Nick Swardson (2003's "Malibu's Most Wanted") are up to the challenge of conspiring some tart one-liners and amiably over-the-top set-pieces, they are less equipped at writing a plot to clothesline the jokes. By the time a major conflict arises—Alex's video game he has created is stolen from him by awkward, emotionally unstable game developer J.P. (Joel David Moore) and passed off as his own creation—the film is already entering its third act. Before this, "Grandma's Boy" drifts rather aimlessly from scene to scene, hitting and missing in the gag department with a basic fifty-fifty ratio.

With nothing really at stake before the climax, "Grandma's Boy" stays afloat—barely—with its strong cast. Allen Covert is just as good as one imagines Adam Sandler could have been playing unlikely hero Alex—high praise, indeed—and makes him into a highly likable presence. The problem with Alex, then, has nothing to do with Covert and everything to do with his own stagnation. By the end credits, there is little detectable growth as a person, and because Alex is basically an all-around good guy from the start, no lessons for him to learn.

As love interest Samantha, Alex's new boss who has been sent in to ensure an upcoming video game is released on time, Linda Cardellini (2005's "Brokeback Mountain") is a delight in an underwritten part. Not much is learned about Samantha, her character developing through her in-the-moment actions, but Cardellini makes the role more than that of the typical "girlfriend" part and exudes charisma, intelligence, and free-spiritedness. Also turning in memorable turns are Nick Swardson, as Alex's innocent co-worker Jeff; Peter Dante (2003's "Stuck on You"), as Alex's overly adventurous, overly tanned pot dealer buddy Dante; and Joel David Moore (2003's "Dodgeball: A True Underdog Story"), whose character of J.P. seems to be channeling a cross between a robot, a schizophrenic, and Neo from "The Matrix." A little of J.P. goes a long way, and a lot of him wears on your nerves, but Moore is nothing if not a unique talent.

"Grandma's Boy" is frothy, consistently silly, and has a genuine enough heart, but it is all in the service of an overall empty package desperately in need of some depth and conflict. As a leave-your-brain-at-the-door entertainment, which is all the film strives for, it is a passable entertainment. With a more focused script and fewer disconnected comedic episodes, though, it could have added up to more. As the first comedy of 2006, one could do a lot worse than "Grandma's Boy." One could also do exponentially better than what this flimsy material ultimately offers up.