Mario Bava is one of the greats of horror cinema, but I wouldn't judge his importance by 'Baron Blood'. It isn't close to his best work. While stylishly directed (to be expected being Bava) and with plenty of atmosphere, it is low on both suspense and gore, and sets up a potentially dynamite premise (the resurrection of an evil Vlad The Impaler-like maniac hell bent on revenge), then goes nowhere much with it. One or two sequences are outstanding, but overall it's a major disappointment, and the usually excellent Joseph Cotton (who did some strong genre work in movies like 'The Abominable Dr Phibes' and 'Soylent Green') is a bit of a let down in the title role. Even so, no Mario Bava movie can be dismissed entirely, and for all its flaws it's still worth watching more than almost all of Hollywood's recent puerile and uninspired horror output.
Review of Baron Blood
