Dr Simon Helder (Shane Briant) is arrested after performing experiments on recently dead bodies stolen from the local graveyard, and is sent to an asylum for the criminally insane for five years. When he gets there, he discovers that the place is being run in secret by Baron Victor Frankenstein (Peter Cushing) who has been believed dead but is in fact continuing his experiments on the inmates...
After the failed comedy style of Horror of Frankenstein, this instalment looked like a reunion of the old Hammer team. Written by Anthony Hinds under his John Elder pseudonym, Hammer coaxed Terence Fisher out of retirement, and Peter Cushing returned in the role that made him famous. However, the nostalgia behind the scenes didn't translate to the screen, and the end result, the last Hammer Frankenstein, was a grey, drab and forlorn effort.
Although chiefly a retread of past glories, the film isn't a dead loss. Cushing's Baron is as icily villainous as ever, with his clipped diction, matter of fact references to "homicidal tendencies" and the like, and drive for scientific breakthroughs at any cost and with no sense of morality. As the film progresses, Helder changes from being his willing disciple to a sickened bystander, thoroughly repulsed by what he had earlier embraced as pioneering. By the end, Frankenstein has become a hopeless case and the asylum is the best place for him.
There are plenty of pathetic souls in the institution; one nice aspect of the production is that every inmate has their own quirks, even the extras. As the prison doctor, the Baron first conveys a sensitivity towards the unfortunates, but it's not long before he's betraying them by exploiting their bodies for his experiments. A lumbering brute who attempts suicide becomes the vessel for artistic hands and the brain of a genius - in Frankenstein's world, talent and skill reside in body parts and God is an irrelevance.
Naturally, it all goes wrong, with the Baron's vile plans for breeding his monster with a mute servant girl (Madeline Smith) amounting to nothing when the creature goes on a rampage. This predictability does nothing to help the film, but the odd item of black humour, such as the Baron accidentally stepping on a discarded brain, helps offset the grottiness of the gore scenes and piteous characters. Not the the best way to end a horror icon's career, but even the film agrees that Frankenstein's time, in this incarnation at least, had passed. Music by James Bernard (of course).