Please help me understand Tobe Hooper's "Night Terrors" (spoilers in OP)

When I rented the video of Night Terrors many years ago, I had high expectations: It was directed by the great Tobe Hooper, and starred Robert Englund of Nightmare on Elm Street fame. And it has its merits – Englund’s performance (sans Freddy makeup) is great, both as the Marquis de Sade and as his distant descendant Paul Chevaller – but as it goes on the plot keeps getting more and more convoluted, like it’s building to something astonishing that ties it all together, and then – what?

What happens is, a young American girl, Genie, is in Alexandria, Egypt, with her father, Dr. Matteson, a Christian archaeologist on a dig. It gradually develops that the Egyptian stud with whom she’s having a fling is a disciple of Chevaller, head of some kind of BDSM will-to-power cult (who is intermittently channelling de Sade’s ghost, by means and for reasons never explained). (Meanwhile, Matteson himself, the hypocrite, is being tied up occasionally by a mysterious prostitute, who also befriends Genie.) Chevaller is keeping an eye on Matteson’s excavation and, when Matteson finds a mysterious box, has him murdered and steals it. (At about the same time, Genie is kidnapped and finds herself chained up in Chevaller’s dungeon.) Chevaller believes the box contain some kind of evidence that will undermine the foundations of Christianity (presaging The Da Vinci Code?), but when he opens it there’s nothing but a set of scales. You know, for weighing things. Much disappointed, he is. At the climax, Genie is rescued and Chevaller carried away by . . . a group of people in what appear to be mermaid costumes . . . another underground cult of some kind?

What did Chevaller hope to find in the box? How would it undermine Christianity?

Who is this other cult? Gnosticism would appear to figure into it somehow (Alexandria being the ancient center of that cult, and then there’s the fish-tail thing).

What do the scales signify? They might have some religious significance – in the ancient traditional religion of Egypt, a dead man’s heart was weighed on scales against a feather to determine if his soul was “light” enough to deserve the good afterlife (otherwise a monster ate him). But no later religion (neither Gnosticism nor Christianity) adopted that symbology, AFAIK.

I take Hooper too seriously as a horror-storyteller to just dismiss this as what happens when the scriptwriter dies in mid-production or something. He must have been trying to tell us some kind of story that makes some kind of sense. But what? Is there some esoteric symbolism I missed?

Looking at his IMDB entry, I think you’re just expecting too much from Hooper. In a career that’s almost forty years old at this point, he’s made precisely two truly great films:* Texas Chainsaw Massacre and Poltergeist, plus one pretty good TV miniseries, 'Salem’s Lot. Most of his stuff has been crap. Well, I could be wrong, I haven’t seen everything he’s done. Maybe Spontaneous Combustion was the Psycho of its day, but I kind of doubt it.

There probably isn’t a good explanation for this film, other than, "Tobe Hooper isn’t that good a film maker, and didn’t really have any idea what he was doing with this movie.

*Actually, Lifeforce is also a guilty pleasure of mine, but I’d say that says more about me than it does about the movie.

Has Hooper ever been interviewed about this film? Ever explained it?

Nobody has a theory?