Joe D'Amato gets a hard time for being a trashy director due to those porn films he made, but he often delved into other genres, and when he got them right, he often blew away the competition. This film, his official debut film (as he did a few Bava-style completion jobs for other directors) is a crazy mix of Gothic Horror and Giallo, and it's a beauty. Also, some people call it confusing, but it's not at all.
At first we see brother Luciano Rossi lamenting the death of his sister Greta, plus we also get a flashback that shows that the relationship was a bit...er...intimate. Next thing you know, Greta's alive and getting involved in a carriage crash outside one of those huge mansions you get in 99% of these films. She's taken in by a sister and brother and examined by doctor Klaus Kinski. Now, Kinski is freaky enough looking, but when he leans over Greta all his veins stick out on his head, and he looks like a Klingon! I digress - Klaus finds a weird necklace on Greta, takes a pin and sticks it through her eyeball, and then leaves, thoughtful. Greta strangely shows no affects of having a pin shoved through her eye and sets her sights on bedding both the brother and the sister.
Around this time it appears that Luciano Rossi is kicking about stalking a member of staff at the mansion who receives a very gory shotgun blast to the face. Yes, someone is out to kill everyone, but is it the creepy butler guy who is spying on everyone? Or the jealous sister, who tries to drown Greta in the bath, then beds her. It's not Klaus Kinski though, because he manages, using something on that weird necklace Greta had, to create a formula that can bring the dead back to life, which not only gets him killed by a mystery person, but also his assistant, and the poor corpse he brought back to life!
I'll stop there with the plot, because what first appears to be a kind of period Giallo ends up being far more sinister. It's like Joe D'Amato thought the genre wasn't strange or gory enough, and packs the film with people with their guts or brains hanging out, others nailed to walls, having their faces slashed to ribbons, or having their eyeballs pulled out by a cat. Being Joe, he doesn't skimp on the sex either, as Greta gets it on with just about everybody. You also get two creepy actors for the price of one, with Kinski and Rossi getting their own space to roll their eyes and be weird. Giacomo Rossi-Stuart looks depressingly aged in this film for some reason.
So once again Joe comes out on top like he did later in the post-apocalyptic genre with Endgame and 2020:Texas Gladiators, and the classic video nasty Anthropophagus. Maybe not so much with Ator The Fighting Eagle, which is a PG rated Conan rip-off that is great for all the wrong reasons.