Published by Souvenir Press, this cover depicts the entrance to 'The Imperial' nightclub - where the main action (and horror) takes place. The real-life Imperial was a fleapit cinema that I haunted as a kid, just round the corner from where the Laws family lived. (Photos of the cinema will follow later).
It closed for business as a cinema in 1963, but in SPECTRE, I reopened it fictionally as a night-club - so what we have here is a cross between an old cinema entrance and a disco-lit foyer. That club is actually called 'Spectres' in the novel - but hey, what's an 'S' between friends?