Martin Durnley (Hywel Bennett), who has a childish alter ego "Georgie", lives with his mother Enid (Phyllis Calvert) and his nouveau riche stepfather (Frank Finlay) whom he resents intensely. Enid dotes on Martin, largely because her first son Pete is a "mongol", and she is afraid that Martin may inherit a similar affliction. One day whilst shopping martin encounters Susan Harper (Hayley Mills), an attractive student currently working as a librarian. When he is caught shoplifting a toy duck baby-faced Martin adopts the guise fo retarded Georgie, consequently Susan takes pity on him and offers to pay for the item rather than create a fuss. This moment of kindness captures Martin’s interest, sowing the seeds of a deadly obsession.
It's taken me far to long to see this, it's availability isn't great and deserves a blu ray release really.
Ostensibly, Twisted Nerve is a dated, politically incorrect British thriller, but if you removed all of the dodgy language you'd actually have a rather liberal film which is trying in a rather ham handed way to show up prudish British values, archaic mental health research, racism and patriarchy.
That said, as a thriller it works well. Hywell Bennett is a nasty piece of work who plays the psychopath convincingly and with menace. His manipulation is calculated and cold and makes for some tense scenes.