"Get a Life" is the "Twin Peaks" of sitcoms -- a certified nut case that ought to find a loyal and like-minded, if not precisely enormous, following. It also offers, albeit inadvertently, an answer to the meaningless query, "What might Bart Simpson be like in 20 years?" That is, if Bart weren't a drawing and couldn't stay 10 forever.

Chris Elliott stars in and helped create "Get a Life," which Fox premieres tomorrow night at 8:30 on Channel 5. He plays Chris (uncanny coincidence!) Peterson, a 30-year-old paper boy who lives over his parents' garage -- as far as he got when they threw him out of the house -- and entreats others to join him in gluttonous feasts of sloth.

Elliott is a graduate of the greatest comedy college in America, "Late Night With David Letterman." Even among all that show's resident zanies, Elliott was the zaniest, whether playing the Panicky Guy or the Fugitive Guy or taste-testing dog food before our horrified eyes.

In his own off-the-wall sitcom, Elliott is doing another variation on the renegade goof who bluffs his way through life, obliviously abrasive, self-obsessed and irresponsible, comic kin to the folksy eccentrics of '30s plays like "You Can't Take It With You." Elliott rejects what '60s rebels rejected, but he does it buffoonishly and without rancor.

In the premiere, Chris lures married pal Larry Potter (Sam Robards) away from job and family and off to Fun Land, the local amusement park where both get deliriously sick on twirly-whirlies and junk food.

For seven minutes of screen time, Chris and Larry hang haplessly suspended from a stalled, upside-down roller coaster. Far below, crews labor semi-feverishly to rescue them. "Henderson," says one workman, "call Thrill World. Find out how they handle their dead." MTV's priceless commodity Julie Brown has a funny cameo as a TV reporter who visits the tragic scene.

Earlier, after Chris and Larry have ridden the Hell Loop 2000 five times and the operator asks if they are "gettin' off," Chris snarls back indignantly, "What the hell does that mean, you filth?" Like most of the characters Elliott plays, Peterson has an infallible talent for missing the point.

In the pilot shown to critics, Chris's mother is played by veteran TV mom June Lockhart. But viewers will see Elinor Donahue (once Betty on "Father Knows Best") in the role. David Mirkin, executive producer and director of the series, said from a sound stage in Hollywood that meddlesome Fox executives didn't want Lockhart and ordered a cast change.

"It's a situation we tried to resist for a long time," Mirkin said with a sigh. "Elinor does a terrific job, but June did a terrific job too. When networks get involved, you have these arguments. This is one we did not win."

There seems to have been no argument, though, about who would play Chris's father: the great Bob Elliott, his real dad, surviving member of the hallowed comedy team of Bob and Ray.

"Gladys," Dad asks Mom on the first show, "were you smoking heavily when you were pregnant with Chris?" In their two scenes, both parents sit at the kitchen table in their bathrobes. As things look now, Mirkin says, this is the way they'll always be seen -- happy sloppy retirees.

"As we move forward, the shows are getting much weirder," Mirkin said. The third episode has just been taped. "It's becoming more and more surreal, which is the way we wanted it, and Chris's character is becoming more a borderline psychotic." Oh good!

"Get a Life" breaks most if not all sitcom rules. And most if not all of them deserve to be broken.

'Queen of Mean'

"One very determined broad" is how Leona Helmsley understatedly describes herself in the rib-tingling, spine-tickling CBS movie "Leona Helmsley: The Queen of Mean," tomorrow night at 9 on Channel 9.

Whence cameth her determination? It seems Mom always liked her sister best when li'l Leona was but a child. So she grew up to be a nasty, abusive hotel magnate and glamorous tax dodger.

The problem with the CBS movie is that all the scenes we really want to see -- the infamous Leona chewing out staff members, throwing tantra and snuggling with her Daddy Warbucks, Harry Helmsley -- are held for the second half. The first half is a boring account of her ruthless rise in the New York real estate racket. Who cares?

Suzanne Pleshette is pretty delicious in the role, but she doesn't get to storm around until the later scenes. Writer Dennis Turner should have started the film (which is based on a book by Ransdell Pierson) with the Helmsley wedding, or with Leona's carefully plotted seduction of Harry. Early stuff about her first two marriages is padding.

Though Pleshette's voice seems about an octave lower than the one Mercedes McCambridge used for "The Exorcist," that only adds to the campy grotesquerie, and the farther one gets into the film, the more lethally Leonal Ms. Pleshette's smeary lipstick and Wicked-Witchy eyes become. The makeup job is terrific.

And so is Lloyd Bridges, bringing a few vaguely Reaganesque touches to the role of Harry, who dumps his Quaker wife of 33 years after Leona purrs things to him like "Lock the door, Harry; I've got another present for you."

To underlings she is considerably less kind. "Are you deaf, or are you stupid?" she snarls at a secretary. A lawyer with bad news is abruptly told "you're fired," as is a security guard with five children whom she finds making a phone call during a coffee break. Wet lettuce from room service at the Helmsley Palace? Off with their heads!

She's a formidable combination of Imelda Marcos, Zsa Zsa Gabor and Papa Doc Duvalier.

And what made her that way? Early on, Mom takes her aside and tells her, "You need too much ... and nobody's got that much to give."

Once the going gets rough, Pleshette gets going. She spits the poison darts with stylish sass. It's too bad the filmmakers didn't give her a better-stocked quiver.

'Against the Law'

There aren't many things the world needs less than another arrogant lawyer, but it gets one tomorrow night with the premiere of the new Fox drama series "Against the Law," at 9:30 on Channel 5.

Michael O'Keefe plays Simon MacHeath, a too-hiply-dressed Boston attorney who dropped out of a tony law firm (like Shannon did on NBC's far less ridiculous "Shannon's Deal") and now runs around town drumming up weirdo clients. In the premiere, he defends a young mental patient accused of murdering his shrink, and helps a Mafia wife almost get a divorce.

The Boston locations are not just nice, but superb -- lots of red bricks and spooky bleak streets. But what happens in the foreground is neither credible nor intriguingly incredible.

MacHeath doesn't march to a different drummer, he stumbles. In Michael Butler's script, he's a nonconformist, a rascal, an unconventional rebel -- but also a blithering incompetent in the courtroom. He really wins his big case by a stroke of luck more than a stroke of genius.

His boorish manner is supposed to be some sign of macho integrity, but it just seems inexcusably crude -- as when he shouts at the mental patient in his jail cell, "Hey, what're you -- nuts, or what?" In an opening scene, he brandishes a zucchini in a courtroom to make the case for a man injured in a masturbation device. O'Keefe makes matters worse with cloyingly smug mugging.

Antiheroes are one thing; irredeemable clods are another. "I don't care what happens," the lawyer's client sighs. Viewers are likely to feel the same way.