This is a very decent movie directed by Alan Gibson, who would later become a second-rate Hammer director responsible for such dreck as "Dracula AD 1972" and "The Satanic Rites of Dracula". It features Judy Geeson, at the height of her loveliness, and Martin Potter, one of the pretty-boys from "Fellini's Satyricon", as a pair of seemingly innocent fraternal twins who come to London and are preyed upon by a crowd of jaded hedonists led by a guy named Clive (who sports flaming red mutton-chops and the strangest English accent I have ever heard).
Most of the movie resembles a more serious version of Pete Walker's "Cool It, Carol", and probably a more historically accurate one too as far as the Swinging London Era of the 1960's is concerned. The movie then veers into psycho territory, however. The twins have an unusually symbiotic relationship and display some psychopathic tendencies, like playing a nasty prank that causes their landlady to fall down the stairs. In the most memorable scene they dress up in bedsheets with only their eyes showing and challenge Clive to tell them apart. The childish game shockingly winds up with an ornamental sword going through one person's neck and everything unravels from there. Some may find the sheer pathos and the unresolved ambiguity of the end a little frustrating, but it makes for a memorable movie is nothing else.
I'd recommend this period because it is genuinely unique movie, but if you like films about Swinging London like "Blow Up" or "Cool It, Carol", or British psycho movies like "Peeping Tom" or "Twisted Nerve" this one should be especially enjoyable
