Val Lewton's final production for RKO's B horror unit is a historical film about the mentally sick inhabitants of an asylum in 18th century London. Boris Karloff is marvellous as the corrupt, devious head of the institution, who shows his charges to the public for tuppence, and is amenable to allowing the enemies of his rich friends to disappear into its dark corridors, for a consideration.
This is an extremely impressive historical drama which isn't scared to show its learning. William Hogarth is given a writing credit and the film recreates frames from A Rakes Progress! The script is witty, intelligent and rich in fascinating historical detail which never even remotely slows down the story. It's not easy to think of an A film that recreates the age nearly as interestingly.
This is a horror film because of the revulsion generated by the enemies of the enlightenment as they not only obstruct change, but imprison reformers within the walls of the living hell. There are brilliant stylistic flourishes: the bare arms snaking out of the bars of the cells in the moonlight; or the flicker of Karloff's eyes as the inmates place the last brick in his tomb.
This is a world of menace and cruelty where evil can be hidden inside a witticism. Where the decadence of the rich is not only accepted, but presumed to be fair. Where the poor suffer unbearably and the pretence of taking care of the sick is a racket. This lost money and Lewton's team was broken up. But his legacy is the best anthology of genre films in cinema.