Although Cauldron of Blood (1970), Isle of the Snake People (1971) and Alien Terror were all released later, Curse of the Crimson Altar (1968) was actually Boris Karloff`s last completed film. At 82, he caught pneumonia (reportedly as a result of his work in the damp manor scenes) and succumbed to it a few weeks after filming.
Alas, Karloff’s swan song is not an ideal exit, even if he is the most redeemable element of Curse. That assessment is completely without nostalgic sentiment. Karloff heads a genre dream cast: Christopher Lee, Barbara Steele and Michael Gough. Stills from the film suggest a potential weird movie lover’s delight, but that potential is squandered through direction and writing that is too pedestrian to even be unintentionally bizarre.
The overall failure of the film can be attributed primarily to the unimaginative direction of Vernon Sewell. Sewell made a spattering of genre films, none of which rose above or fell below the level of mediocre. The plot, inspired by Lovecraft, is well-worn. Robert Manning (Mark Eden) is searching for his missing brother, Peter. This search leads Manning to Craxton Lodge. There, Manning encounters resistance and denial from J.D. Morley (Lee). Lee is overly familiar here in the type of sinister, square mustachioed role he played repeatedly. Although his acting is by no means unprofessional, the way his role is written, coupled with lackluster direction, leaves no opportunity for surprise.
Feigning guilt for his lack of information regarding Peter, Morley hospitably invites Manning to stay at Craxton Lodge. Manning does, partly because of amorous ambitions for Manning’s niece, Eve (Virginia Wetherell), whose wardrobe alternates between mini-skirts and see-through nighties.
The film spins (wastes) a bit of time following Manning’s attempts to bed Eve (predictably, he succeeds). Meanwhile, Manning has nightmares regarding Lavina Morley (Barbara Steele) and his deceased brother. Lavina was an ancestral witch, burned at the stake, who now seeks revenge on the descendants of her persecutors. Shockingly, Manning discovers that his own ancestor was Lavina’s chief prosecutor! That sounds a bit like recycled Mario Bava for a reason. The casting of Steele is a complete wash out. She is wasted in green make-up, a low cut dress, rams’ horns, and a laughably bad echo box . It is little wonder that this film inspired her attempt to get the hell out of a genre that had degenerated into trash.
The dream sequences follow a mundane S & M formula. A tasseled dominatrix whips her virginal victim, and Lavina’s henchman, in studded leather bikini briefs and Harley head gear, brands victims with the mark of Satan! Throw in more half-naked virgins, banal color wheel lighting affects, a spinning sixties lamp which channels the dead, and some spirograph fx and juxtapose all this with scenes of late 60’s youth whittling away their lives with drugs and orgies. Obviously, such a rock-n-roll culture spawns from Old Nick himself, who is pulling the strings in the form of Lavina, exacting her revenge. If that sounds like a possibly entertaining cup (and to some it might), the disappointment inevitably comes in how lethargically it plays out.
Michael Gough is the imbecile butler, Elder,who appears sporadically to issue warnings of doom. George Zucco used to sleepwalk his way through parts like these, and Gough fares a tad better (mainly, with hammy, bushy brow antics).
The one source of genuine surprise is Karloff as Professor John Marsh. Karloff indeed looks gravely ill here. His eyes are sunken and his countenance is emaciated enough that his hat, coat, and blanket threaten to swallow him whole. He acts mostly from his wheelchair and, although he is understandably given little to do, with assistance from his “I wear my sunglasses at night” mute chauffeur manservant (Michael Warren), Karloff injects a sense of menace into the part.
Karloff scowls with disgusted boredom over Manning’s lack of wine-tasting finesse, but the professor’s interest is perked when he discovers that the hipster is an antiques dealer. Marsh invites Manning to see his collection: instruments of torture. Karloff plays the scene with the right amount of condescension and personality, and doesn’t kill it with overplay (unlike, say, Lugosi in 1935’s The Raven).
The novelty of this being Karloff’s final film is not enough to salvage the enterprise, although the film, posthumously, retains minuscule interest as an of-its-time curio (yesterday’s trash is more tolerable than today’s trash). Villagers celebrating Independence Day, villagers playing hide-n-seek, an attempted human sacrifice, and self-immolation are inexplicable ingredients in this woefully under-developed brew.
A flaming finale usually guarantees a degree of oomph, but, as with the rest of the film, this one fails to emerge from a nitric coma. The sprightliest moments are somehow produced by a terminal veteran actor trying to make his way towards the end credits.
Alfred Eaker 
Yesterday’s trash is indeed better than today’s trash.