Graham Williamson’s review published on Letterboxd :
The Conservative philosopher Roger Scruton once defended the (pre-Blair) House of Lords on the grounds that the hereditary principle was more representative of the character of Britain than direct democracy. Whereas elected politicians, he argued, would inevitably be more ideological, cunning and intelligent than the ordinary Briton, the House of Lords selects by an accident of birth, ensuring a completely random mix of brilliant minds and total idiots. There's a similar principle at work with the Video Nasties list. There was never a consensus on where the line should be drawn between a horror movie and a video nasty, and the Department for Public Prosecutions showed little interest in researching the genre. Useless as an index of the most extreme horror movies, the Video Nasties list is instead a useful cross-section of the state of low-budget horror in Europe and America from 1963 to 1983. Its value lies in being a completely random selection, unencumbered by analytical thought.
Mario Bava's Bay of Blood, for example, probably isn't Bava's goriest film. It's certainly not his best film; the plot is over-convoluted and there's a reliance on bluish natural light, which I find is always a disappointment in a giallo. I want them as artificial as possible, and if that means tripling your electricity bill then so be it. But it offers a pretty good snapshot of the pleasures of mid-tier Bava, and why mid-tier Bava is still a cut above. For all its infrequency the violence still makes you catch your breath when it comes. There's a fantastically tasteless scene where a couple having sex are stabbed, and their dying gasps sound almost indistinguishable from the noises they were making earlier. The sex and death link has rarely been so blatant.
I'm not sure the mixture of complex inheritance plot and gruesome violence really works, but it's undoubtedly the sort of bizarre mixture that makes this era of Italian horror distinctive, and Bava remains one of its greatest practitioners. Those interested in ticking off genre trademarks will enjoy Stelvio Cipriani's easy-listening score, which as ever in Italian exploitation is so wrong it's right. It's not where I'd start with Bava, but thanks to the free publicity offered by the DPP list it is probably the first one of his films a lot of Britons saw. And thanks to the DPP list's shoddy research it's pretty representative.