This is an extraordinary film, in which the Russian court is reimagined as a grotesque, surreal fantasy world, peopled by buffoons and conspirators. The sets are the stuff of nightmares... it's as if Alien's designer H R Giger was let loose on Gormenghast castle.
The mood lurches from farce to pageant, from horror to comedy, and the performances are wildly over-the-top; in one memorable instance Dietrich is transformed from guileless princess to plotting vamp within minutes, jettisoning her little-girl-lost voice and adopting her trademark smoky, seductive accent.
The film displays not a shred of historical accuracy; this is a fairy-tale, and one that's genuinely unforgettable. The drill-bit emerging from an icon's eyeball, the skeleton at the feast, the emperor's pop-eyed manic leer, and Catherine's rictus grin as she caresses her steed - these and other scenes linger long after the closing credits.