A whole bunch of reprehensible people turn up at a disused theatre on the night of rich aristocrat Patrick Devenant. These people are your usual Euro-film bunch of double crosser and promiscuous deviants: there's a few lesbians, a married couple, a couple who want to get married. That kind of thing, plus all the usual infidelities. The theatre is run by a creepy guy who turns up to spout something dodgy about the people or the theatre, then disappears again.
It comes as no surprise that a black-gloved killer or killers is/are on the prowl and the first guy to nearly get it is Patrick, who narrowly dodges a huge wooden block that's dropped on his head. Naturally this prompts a lot of discussion from everyone about how much money Patrick has and who would want it. When the first victim is stabbed in the back while performing Romeo and Juliet on stage, the rest of the folks discover the phone lines cut and the door locked. They now have to spend the whole night together and one of them may be the killer...
I've got to admit to being a bit underwhelmed with this one. Too much jibber jabber and not enough...err...dibber stabber. Overlong to considering the premise, with many scenes content to have the actors endlessly discussing what's going on, blaming each other, putting the moves on each other, or wandering off alone to get murdered by a killer who wears a mask that makes him/her look like Alan Sugar. There's plenty of nudity however, but that just serves to slow down things even more.
It's not a total loss, however. There's a nice supernatural angle to the film where the curator of the theatre might be a ghost, disembodied voices call to the actors, and there's a confusing bit where a dummy looks alive...for a second or two. We also get a strange painting that depicts the fate of the character and the whole theatre setting gives the film a nice gothic horror feel.
What it needed more of was random daftness and poor taste - we do get one character throwing caution to the wind, necking a bunch of pills, and dancing around naked in the middle of this murder fest, and there's a bit of nastiness when someone has their hand nailed to a post, but there's too much talk for me. An okay giallo, but not a great one.