Compared with the usual "Masterpiece Theatre" offering, "The Bretts" is the pits. And yet the eight-part serial, premiering tomorrow night at 9 on Channel 26 and Maryland Public TV, has, to quote a phrase from its dialogue, "a certain jejune charm." Objectionable and unpleasant people can, after all, still be entertaining.

The tragi-farcical saga of a fictitious British acting clan trudging through the 1920s, "The Bretts" was created, and its first chapter written, by Rosemary Anne Sisson, a key collaborator on "Upstairs, Downstairs." Shamelessly and derivatively, she keeps bringing in the Bretts' servants to comment upon the crazy doings of the family members, the old "Upstairs, Downstairs" gambit revisited.

Unfortunately, these servants happen to be bores, existing merely as a device, and Sisson should take an oath never to use it again.

Barbara Murray and Norman Rodway play Lydia and Charles Brett, founders of the dynasty, such as it is, partners in a marriage with fairly loose ground rules. One son, Thomas (George Winter), turns out to be the product of a previous dalliance by Charles, and when Thomas finds out, he gets as mad as a wet hornet. Since he's a petty, sulking little prig anyway, one isn't much concerned.

Even allowing for the inbred chilliness of the British, the family as portrayed seems lethally disputatious. The word "love" is never spoken in this house. Lydia and Charles quarrel over a secretary in Part 1, then quarrel over the hiring of a chauffeur in Part 2. Daughter Martha (Belinda Lang) insults and is insulted by brother Edwin (David Yelland) and both pick on poor Tom.

A sweet if lonely breath of spring is provided by the delicately pretty Lysette Anthony as Daphne Villiers, Thomas' half-sister, cast in a play on the suggestion of a calculating businessman who came into ownership of several theaters more or less by accident.

While it could certainly be said that the Bretts are a tiresome lot of brats, they're still on some level forgivable, in part because the theatrical tradition they personify is a bit on the doomed side and they're living in self-absorbed obliviousness. The talkies lurk just over the painted horizon.

Various writers and directors worked on different installments of the series, contrary to the norm for this sort of thing; the result is like a computer-generated version of a Noel Coward romp. As a production, "Bretts" exhibits the fastidious attention to detail one expects. But the scripts really don't seem half as admirable or inventive as, say, those for "The 'Slap' Maxwell Story," produced for (how vulgar!) an American commercial TV network.

According to publicity, "The Bretts" was "based on an idea by Herbert Schmertz," the learned Mobil superflack. To judge from the first few chapters of the serial, which is neither masterpiece nor theater, basing something on a Schmertz idea is a bad idea. Still, the old boy is entitled to some homage for all Mobil's years of generous PBS funding and enlightened programming.

Also meriting an accolade, and getting one, is the late Joan Wilson, executive producer of "Masterpiece Theatre" for WGBH in Boston from 1973 until 1985. "The Bretts" is dedicated to her.

'Women in Prison' Fox Broadcasting Co. has done it again: made another dreadfully wretched TV sitcom. They seem to think there's a shortage of mediocrity in the world and are doing their utmost to correct it.

At least "Women in Prison," premiering at 8:30 tomorrow night on Fox's Channel 5, has a bright moment or two, the brightest of them provided by roly-poly Wendie Jo Sperber, who ran merry riot in movie comedies like "1941" and "I Wanna Hold Your Hand."

Sperber plays one of the women in the cell block where this belabored sitcom is set. Among the others are Peggy Cass (returning to series TV in this, of all things), C.C.H. Pounder (she of the terminally withering gaze), pinchably plump Denny Dillon (briefly a regular on "Saturday Night Live") as a guard and amateurish Julia Campbell as Vicki Springer, a ditzy WASP princess tossed into the slammer on a trumped-up shoplifting charge.

Vicki's idea of a nasty epithet is "Eat clams out of season!" Alas, Campbell is the worst, least and most uninteresting actress on the premises, a garishly incompetent mugger -- so naturally she gets the lead role. Sperber, previously a happy fixture on "Bosom Buddies," has only a couple of scenes, but the one in which she pounds out "Tie a Yellow Ribbon 'Round the Old Oak Tree" on a Hammond organ is priceless.

Otherwise, the humor waxes smutty and wanes dumb, with the comic terrain dominated by lesbian jokes, toilet-cleaning gags and prison brutality knee slappers.

The Fox folk proudly note that the series was produced by the creators of "Married. . . With Children." That series is running out of whatever steam it once had, and here are the producers wandering off to do another! Fox really ought to recruit some new creative talent -- maybe from among the bag boys at Ralphs or the valet parkers at Spago.

There's a bellhop at the Beverly Hills Hotel who's pretty funny.

Commedia del Cable People with cable have more laughs than people without it. Not just those bitter laughs of resignation when the darn thing goes off right in the middle of the David Letterman show, either (as Arlington's ever-makeshift system did almost every night this week, grumble grumble).

No, in addition to that, Home Box Office plays host to a continuing golden age of stand-up, with cut-rate competitor Showtime not too far behind. Tonight at 10, HBO premieres "The Eleventh Annual Young Comedians Show" and Showtime unveils "Elayne Boosler: Broadway Baby." You'll laugh, you'll yuck, you'll spill your Tang.

You may even pay your cable bill with less resentment than usual.

Five young comedians sashay through HBO's special, at least four of them darned interesting as well as funny. Best by far is woebegone Margaret Smith, not so much deadpan as comatosepan, dry and caustic and subtle -- a living anatomy of melancholy. "I wore a neck brace for a year," she says. "I wasn't in an accident or anything. I just got tired of holding my head up."

Geoff Bolt, second on the bill tonight, sneaks up on you with a bizarre, subconversational rap. Bolt doesn't just tell jokes; he fills in a paint-by-numbers portrait of abject dementia. He accomplishes this with the help of a marvelously hapless hand puppet named Bobby. Comedians are a dime a dozen now, and overpriced at that; Bolt is a definite No. 13, and genuinely original.

Allan Havey, who opens the show, needs a word like "penis" to get a laugh (which must be what that word is for). Bobby Slayton, who has a Broderick Crawford voice, makes remarks about Puerto Ricans and Chinese that are more derogatorily childish than funny, though his re-creation of an encounter between an old Jewish woman and an old Chinese waiter is amusingly accurate. And Rick Ducommun, last on the show, is a good, reliable, nuts-and-bolts laugh-getter.

Only Ducommun does material that is overtly topical -- the Bakkers, Delta Air Lines, Gary Hart, Ronald Reagan -- but the show doesn't lack for '80s zeitgeist. With all the talk about safe sex and anxious ennui, it earns a spot in a comedy time capsule. Rocco Urbisci, the director, never calls an errant shot.

Far less satisfying is Showtime's Elayne Boosler special. Does the comic really deserve a one-woman showcase on Broadway? It took Robert Klein, who's much funnier, years to mount such an opus. Boosler needs seasoning. And humility.

She begins the show with her autobiography in photos and narration; it seems she always dreamed of success in show biz. Gosh, what a fresh notion. Then she dances around New York singing Stephen Sondheim's "Broadway Baby." The ornate prelude is supposed to disguise the fact that what we have here is a very very long one-person comedy concert.

Jokes cover dating in the sexually paranoid '80s ("maybe we should just use jumper cables"), the purchase and advertising of condoms, TV preachers, dogs, contact lenses and alternatives to natural childbirth ("I'd have it quick and neat. I'd have Heimlich").

Not until about halfway through the show, when she begins delineating the differences between men and women, does Boosler really bop. Men, she explains, were born without a "shopping gene"; women have no biological need to jump up and touch an awning when walking down the street. She's also funny on the irresistibility of diet temptations. A pint of Ha agen-Dazs is supposed to serve four, she says, then laughs guiltily and gleefully to herself. Surrrrre it is.

Steve Gerbson, who produced and directed, chose not to light or shoot the audience in the theater, so the program, once past its outdoor opening, seems visually constricted, even suffocated. We just watch Boosler march back and forth across the stage in some sort of Naugahyde Barbarella garb, talking and talking and talking, until she begins to seem like an annoying panhandler who won't let up until proffered a quarter.

A half hour of Boosler would have been plenty. In her notorious deodorant commercial she says, "Never let them see you sweat." Some more advice: Never let them see you run out of material, either.