I finished this Roger Corman-directed 60s horror last night, and really enjoyed it once it picked up. The central performance from Vincent Price as a Satanist Italian prince is fantastic, and well worth the price of admission alone. Probably the best I've ever seen from him. I really enjoyed his delight in the suffering and humiliation of his subjects. Jane Asher is also great as a morally-grounded innocent, ripe for corruption.
It's an adaptation of an Edgar Allan Poe short story and I swear I read last year (maybe even here) that it had been given a boost in popularity by the coronavirus pandemic. The parallels are pretty stark, albeit also perfectly predictable with the elites shutting themselves off in safety, decadence and depravity, leaving the peasants to die of a ghastly plague.
While it seldom escapes the feel of a lower-budget 60s movie made in Britain, it's beautifully photographed by Nicolas Roeg. The colours and costumes are spectacular, and the monochrome rooms of the castle are fantastic, moving through yellow and purple, red and black. Very eerie but beautiful.
Here's an interview with Roger Corman and Jane Asher from last year, following its resurgent popularity:
https://www.theguardian.com/film/2021/feb/08/how-we-made-jane-asher-horror-classic-masque-red-death-vincent-price-roger-cormanRecommended.