The premise of "What Planet Are You From?" is one of great convolution and foolishness, the type that, more often than not, would simply be written off as a dimwitted movie without any value or merit. Who could possibly take a film seriously in which an alien (Garry Shandling) from a planet "way the hell out there" is sent to Earth for one mission, and one mission only: to mate with a woman and have a child? Sounds like the usual low-rent junk that is released in theaters in the spring, or sent direct-to-video, eh? Certainly not, if it aims directly for laughs, and is in the hands of acclaimed director Mike Nichols (1983's "Silkwood," 1988's "Working Girl," 1998's "Primary Colors"), and stars, among others, Garry Shandling (TV's "The Larry Sanders Show"), Annette Bening (1999's "American Beauty"), and John Goodman (TV's "Roseanne").

Following a prologue on the distant planet, where the human-looking aliens (who otherwise exhibit no ability to have feelings or emotions) are misdirected in their teachings on how to treat the opposite sex, one such alien, who is given the name Harold, is chosen to make his way down to Earth. Locating himself in Seattle, Washington, he gets himself a job at a bank and makes friends with his womanizing, married coworker, Perry (Greg Kinnear), who begins to help him in his quest to meet a woman. Harold, who firmly believes he can have sex with a woman if only he compliments her on her shoes or hair, has another problem, which is the brunt of a great many jokes, almost all of which are a devilish hoot: when aroused, his penis vibrates and makes a buzzing sound.

One evening, Perry takes Harold to an AA meeting (a prime place, Perry believes, to pick up conflicted and vulnerable females), where Harold is instantly smitten with Susan Hart (Annette Bening), a recovering alcoholic/real estate agent whose biological clock is ticking very loudly, but who has sworn to herself she will only sleep with someone again when she has married. After just one date, in which Harold and Susan hit it off, Harold proposes marriage to Susan, and in a moment of haste, she accepts. Their relationship soon grows problematic, however, when Harold becomes very distant and unloving towards Susan after she has gotten pregnant. What she doesn't know is that he isn't purposefully being emotionally cold to her: he just doesn't know how to love.

Meanwhile, following a mysterious blast on an airplane that allegedly was Harold's entrance to Earth, a Federal Aviation Administration agent (John Goodman) begins to investigate the strange occurrence, and gradually catches on to the true identity of Harold, causing stress on his own marriage to a fed-up housewife (Caroline Aaron) who believes he is having an affair.

"What Planet Are You From?" may very well be the trickiest motion picture of the year, thus far, because its admittedly ludicrous nature only adds to the delicate balancing act that must constantly be obtained by director Nichols and screenwriters Garry Shandling, Michael Leeson, Ed Solomon, and Peter Tolan. One prominent misstep, and the whole film would be in danger of crumbling to the ground, making the movie be a complete embarrassment for all involved.

It's a stroke of luck (and an obvious boatload of comedic talent), then, that the film is, overall, the most laugh-out-loud funny comedy in ages. For the first hour, it is genuinely perfect, a masterwork in which literally almost every attempt at a laugh works, so much so that I often was still laughing at one part, when the next would arise and make me laugh even more. Suffice to say, I wasn't able to inhale much oxygen during that sixty-minute time span. Everything, even right down to the use of a particular musical chord that echoes the raising of a character's eyebrows, is an example of comic brilliance, the way all comedies should work. Refreshing, too, that a movie with countless sex and penis jokes manages to avoid being overly juvenile, and is aimed squarely at teenagers and adults. It may be silly, and it may sometimes be even graphic in its sexual innuendo, but it is also an undeniable riot.

The second hour of "What Planet Are You From?" shifts tones, and while still effective, much of its comedy is put on the back burner for a more somber, poignant look at love relationships that may involve an alien in this case, but stands for a great deal of marriages, in general. Changing from something that is so highly entertaining and relatively breezy to something that delves a little deeper into the characters and story comes as a marginal disappointment on the outset, but in another way, the latter half is vital to what the whole picture has been setting itself up for. By getting more serious, but never totally abandoning its comedy, director Nichols wants us to invest our feelings into the fate of Harold and Susan's relationship, and we are surprised to realize that, while the opening had been wavering along the lines of even being considered a spoof, a 'la "The Naked Gun," we have, indeed, grown to care about them.

Only the climax, which briefly takes us back to Harold's planet for a rather saccharine speech on the importance of compassion and human emotions, does the film stumble for more than a fleeting moment, but, fortunately, it recoups itself by the finale.

Garry Shandling, in his first starring film role, is outstanding as Harold, the very important and flawless comedic center of the film. While being unable to feel things inside, Shandling, nonetheless, is able to gain our sympathies, and the eccentric romance that blossoms between he and Susan is sweet-natured and involving. Susan, as played with energy and appropriate pinnache by Annette Bening, is Harold's total match because, although she gradually becomes dissatisfied with his uncaring ways, makes it clear that she had meaningless sex with so many men in her life that she has forgotten herself how to love, or what it even is. Only after meeting the one-of-a-kind Harold does she start to rebuild her life and understand what it means to feel love, even when it isn't outwardly being returned to her.

As the slimy Perry, this is Greg Kinnear's most memorable role to date. Usually an extremely bland actor, Kinnear jumps off the screen here and makes his, albeit unlikable, character come alive. Judy Greer (1999's "Jawbreaker"), as a flight attendant turned off by Harold's advances until she meets him at the AA meeting, is entertaining and gets a great big laugh in the last second of her final scene due to the aforementioned musical chord that strikes at just the right time. And although just an unbilled cameo, Janeane Garofalo brings her usual sparkling presence to the role of a nervous flier whom Harold hits on, even in her horrified state. Meanwhile, Linda Fiorentino (1997's "Men in Black") is severely wasted as Perry's wife, who Harold considers having an affair with after he is married.

Whatever you do, do not be turned off by the premise, or the title itself, of "What Planet Are You From?" Rated R, and rightfully so, this film will delight adult viewers who are in the mood for a feel-good comedy that turns out to not only be about the punchline of jokes, but also, within the context, takes its characters and their situations seriously. In fact, perhaps the most gratifying thing of all is that director Mike Nichols and his cast of high-profile actors took a big risk on making this offbeat movie, and do not embarrass themselves. Not one little bit.