You have to give credit to the nutty guys behind “Terrorvision” (citywide with “Zone Troopers”), a fitfully funny new horror spoof from the Empire production line. The idea of another shocker about aliens leaping out of our TV sets (shades of “Poltergeist”) must have seemed so preposterous that the film makers shrewdly decided to play it for laughs.

There are a few wonderful moments scattered throughout the picture, clearly the kind of goofy monster mash that should be seen long after midnight when your brain is operating at half-speed. After all, it’s hard not to like a slobbering, deliciously disgusting beast that escapes from the Mutant Creature Disposal Unit of planet Pluton’s Sanitation Department. Writer-director Ted Nicolaou also dreamed up the inspired notion that the family under fire should be just as bizarre and--well, moronic--as their guest from outer space.

But to mix up gross-outs with gags you need a good curve ball--the jokes should have a real spin to them. That weird comic rhythm is missing here. In fact, Nicolaou has such a terrible sense of timing that the scenes drag on long after every laugh has been squeezed dry.

The movie certainly has an enticingly campy premise. Stanley Putterman (Gerrit Graham) installs a new satellite dish that pulls in every TV signal imaginable, including some wayward cosmic energy that beams an ornery monster into his living room. When the mutant’s master appears on screen, warning of impending danger, everyone assumes he’s just a character in another crazy cable-TV horror film.

Many families might sense something is amiss, but not the Puttermans, a dazzlingly dimwitted clan whose home is adorned with tacky fountains and neo-pornographic art (that art director Giovanni Natalucci has cleverly designed to look like mock Nagle paintings). Grandpa (Bert Remsen) is a dithering survivalist who munches on lizard tails. Dad and Mom (the delightfully imperious Mary Woronov) are swingers, eager to bring another Fun Couple back to Chez Putterman for a splashy night in the jacuzzi.

With the parents away, the taming of this shrewish monster falls in the hands of the Putterman progeny--Sherman, a paramilitary brat, and Suzy (Diane Franklin), a new-wave coquette with a boyfriend named O.D. and a towering hairdo that looks as if it could do double duty as a thatched hut in the tropics. It’s an appealing notion that the future of Western Civilization should be left in the hands of these lame-brained kids, especially since they seem peculiarly tuned in to the monster’s spacey wavelength. But too often, Nicolaou’s disjointed pacing and clumsy gags spoil his satiric aims.

“Terrorvision” (MPAA-rated: R) is purposefully bad, but not truly bad enough for us to throw away our popcorn and join the fun. The secret of high camp is that you have to earn your laughs without really trying.