_The Invisible Maniac_ is a silly horror/comedy boob fest.
Within the classic Universal monster movies, _The Invisible Man_ (1933) is one of the worst. I typically hate comedy in horror, yet I tend to like horror comedies. What I'm saying is this is a superior invisible-man story.
The story is routine: a scientist makes an invisibility serum, then goes mad... or in this case, even more mad.
This is actually made well, considering it's a goofy flick that you would have seen on late-night HBO, back in the day.
The acting might be the only truly weak part: I can remember at least three scenes were actors flubbed lines. You're not going to get another take? No? Okay.
BOOBS!
I think Peter Duhamel was great as our mad scientist. What a missed opportunity that he was never cast as The Joker in a film or cartoon.
Everyone else does an okay job. Debra Lamb has the best set, and the movie even has porn star Savannah.
Totally recommended to anyone who likes dumb boob comedies from the era.

Post script: What mad scientist is complete without a test rabbit? Yup, anytime I see a rabbit in a movie, I get nervous. There is a scene, at the end, where Mister Bunny's cage is thrown; now, I doubt they had a live rabbit in the cage for that - seeing as how the scenes where he was injected with serum, it was clearly acted; meaning, a needle never touched him - but this was 1990, and there wasn't a "no animals were harmed during the making of this film" in the credits, so I can't say.
What is certain is animals are still tested on, to this day, and people pay for it to continue. When you buy personal-hygiene products, and cleaning products, if they do not specify that they are cruelty free, you are paying for animal abuse.