3rd Rock from the Sun, on NBC
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So there were these aliens on an expedition to study life on Earth. They assumed human form for the mission, and posed as a family. The High Commander called himself Dick Solomon (John Lithgow), and took a job as a college physics professor (though his class was constantly frustrated that he tried to teach things which were ridiculously beyond the scope of current human knowledge of physics, and he was constantly frustrated that they didn't get it). The team's information officer (the oldest member of the crew) was called Tommy (Joseph Gordon-Levitt), and took on the form of a teenager, ostensibly Dick's son, who had to attend high school. The security officer (a lieutenant, and Dick's second in command) took the name Sally (Kristen Johnston), assuming the form of a woman, Dick's sister (apparently their species' actual forms are asexual, and very different from humans, physically). The final member of the team is Harry (French Stewart), ostensibly Dick and Sally's brother. For quite awhile it seems he doesn't actually have a role in the mission, per se, but we eventually learn he is a transmitter, and the others can communicate through him with their boss, "The Big Giant Head," back on their homeworld, I guess. There are a number of important human characters on the show, including Mary Albright (Jane Curtin), another professor at the university where Dick works, with whom he develops a romantic relationship. There's also Mrs. Dubcek, the Solomons' landlady. And Nina, who is Dick and Mary's administrative assistant. And Don Orville (Wayne Knight), a cop who develops a romantic relationship with Sally. Also, Tommy had a couple of different girlfriends over the course of the series, one named August, and later one named Alissa (Larisa Oleynik).
Anyway. So. Dick was generally quite childish, and Sally quite militaristic, and Harry was just really weird. Tommy was the most normal one in the group, though often frustrated by his crewmates and by having to act like a teenager, himself. But none of them really understood humanity very well, thus hilarity ensued. I'm not really sure what else to say, it's just sort of your standard gelatinous-purple-tubes-out-of-water story, really. A comedy of errors... and oh my, were the Solomons prone to errors. I suppose you could also say the show held up a mirror to the oddity of human society, from a far, far outsider's perspective... but still, it was hard to tell, because the aliens were so odd, themselves. But it really was rather a hilarious show.
And I guess the only other thing I wanted to mention was that at the end of the second season, there was a 2-part episode that aired in 3-D (I still have at least one pair of the glasses that were distributed, though I don't recall exactly how they were distributed). Anyway, in these eps, each of the aliens had a dream, for the first time. I kind of feel like they might've mentioned dreaming before that, so... I could be wrong, or the writers could have overlooked it. I dunno. In any event, I quite enjoyed Harry's dream, a rather lavish production in which he sang a cover of Randy Newman's "Life Has Been Good To Me". So now, years later, I have made an mp3 of that song, as a public service. In case you're interested, just click the preceding link. You're welcome.