Well, that came out of left field, as they say in America. "3rd Rock From The Sun" is a real breath of fresh air, a jazzy jolt to the senses and a little different from what's been around recently. It's been a huge hit in the States, despite its abrasive style and relative lack of cheesy moments, but exactly what reception it's received here remains doubtful. We like our American comedy sharp and sardonic with a nice touchy, feely bit at the end - see "Friends", "Frasier" and everything else - and "3rd Rock from The Sun" may be sharp but its humour is based on wordplay of a more juvenile style. Plus there's a heavy element of clowning around that's just plain silly. The trick to watching this show, if you're willing to give it a try, is to empty your head of intellectual thoughts and become a sniggering teenager again. If you are still a sniggering teenager, you'll love this stuff.

It has shades of "Mork And Mindy" in its rapid-fire script, but the Solomons' alien-ness is more defined than Mork's and they are less sympathetic characters. The series also bears a passing resemblance to "Red Dwarf" with its irreverent streak, yet is far funnier and doesn't rely on some special effect or other to bolster the content of each episode. The resulting mixture is a great menu of slapstick, wit and sarcasm that has all the makings of a classic. Plus its human characters are as crazy as its alien ones anyway, which makes for a minimum of 'gosh, aren't these people strange?' scenes.

The writing is bright and brassy, weaving through sight gags, 'Carry On'-style slapstick and some sharply-observed moments, plus a dose of close-to-the-bone humour that treads within touching distance of what you're not supposed to do. Even the odd swear word creeps in. The series' attitude to women has already been singled out for criticism, yet the female characters are just as strong as the male ones and the humour is the sort of ribaldry you'd find on a lively night out. In fact, while it avoids dollops of schmaltz and obvious 'lessons', the writing has given a sweet, well-meaning core to "3rd Rock From The Sun" which allows you to wallow in the Solomons' foibles without guilt.

If the series is well written, it was cast by a genius. It's like one of those classic Britcom series like "Fawlty Towers" or "The Fall And Rise Of Reginald Perrin" where every character has some eccentricity to contribute and gets their chance to shine. It's especially good to see John Lithgow enjoy success after to many strong supporting roles or main parts in lesser films, and he's already unleashed his playing talents to the extent that he's won an Emmy award for Dick Solomon. The effort he puts into one episode is the equivalent of a series' worth of other programmes. Dick is vain and pompous, has the literal perception of a child, and allows Lithgow to throw himself at matters with skill and energy. Kristen Johnson plays Sally (who's really a male alien) and pitches both male and female traits perfectly in what's a tricky role. French Stewart is Harry, a Forrest Gump-esque ingenue who could easily be overplayed but he pulls back from that, leaving an endearingly loose cannon of a character. Joseph Gordon-Levitt is Tommy, the oldest alien in the body of a fourteen year-old boy, and manages to combine the stern man and the hormonally active boy with chutzpah. Together, the four of them are an unstoppable whirlwind of unpredictability.The human characters don't get left behind either, with Jane Curtin's Mary achieving a perfect balance between being incredulous and wary of what Dick will do next.

The series has a house style that verges on the frenetic, and a weird pacing that carves its own identity and keeps going off at tangents, while it seems to back away from just focusing on one character and giving them a dilemma to sort out. There are moments too - and these are the very best bits - when the show seems more like a cartoon with its syncopated rushing about and expressions.

"3rd Rock From The Sun" is vibrant, funny, and a great leap away from the usual 'dark' sci-fi series, with a mixture of knowing and innocence that makes it a rewarding watch. Unlike other comedies, the message is left in the plot for you to either get or not; in fact the rooftop endings often show how the family have misunderstood things totally. And let's face it, no matter how weird "The X Files" tries to be, it could never come out with anything to match The Big Giant Head.