Carlton Cinema
The Carlton Cinema on Tottenham Court Road, along with the Majestic, had the worst reputation for men 'importuning' in London at the beginning of the twentieth century. The crowded dark gangways offered opportunities for men to meet close-up.
"the chief immorality... Goes on in the queues adjacent the wall inside... A lad or young fellow standing sideways against the wall would place his linked hands behind him with his figures turned outwards... Over and over again men would come to such lads, generally with a mackintosh or overcoat on their arm thus screening their actual movements.
It is for this very reason that lighting was introduced in cinemas, running down the gangways. The London Count Council (LCC) expanded their regulation of cinemas by requiring "shaded lights along the side so audiences could see each other".
Other West End cinemas where men would have sex included the Cyril, Cinema de Paris, Cupid (Leicester Square), the Paper (Cambridge Circus), Gaity (Tottenhamm Court Road), Arena (Villiers Street), and Super (Charing Cross Road).
References
Queer London – Perils and Pleasures in the Sexual Metropolis, 1918-1957 Matt Houlbrook, The University of Chicago Press, 2005.