A Film Canon

This superb film turns on roughly the same premise as And Then There Were None, but nuances it further in the direction of a proto-slasher aesthetic. Most generally, Siodmak suffuses the (largely housebound) action with a mild hyperbole that lends an ambiguously supernatural aura to the killer. More subtly, by debilitating most female members of that household - a mute chambermaid, a drunken cook, a dying matriarch - and specifying that the killer's modus operandi is a taste for such debilitation, screenwriter Mel Dinelli ensures that the voyeuristic pleasures of his crimes are raised to a sexual pitch, anticipating the masses of dead teenage bodies to come, and beautifully encapsulated in the opening murder, which takes place against a screening of Edison's The Kiss. However, the most impressive gesture is Siodmak's poetic subjectivisation of the house - and, more specifically, his transformation of it into an extension of the killer's giant, omnipresent, aqueous eye, which incorporates everything into its hallucinatory, vertiginous scheme, of which the eponymous staircase is the mere epitome, or culmination. For this reason, horror tends to stem either from the characters' isolated immersion in fluid, connective spaces (corridors, staircases, porches), all of which represent so many variations on the aquarium that preoccupies the master of the house, or from their concomitant failure to recognise the extent to which their 'safe' rooms and communal areas are couched in such liquidity; that is, the extent to which the plot-long storm pervades and infiltrates the house, explaining the profound terror generated by a perpetually, and mysteriously, opened upstairs window.