Hammer house Of Horror: The Two faces Of Evil.
A family on holiday pick up a mysterious hitch-hiker who attacks the driver and the car rolls over. In a hospital the wife is told her husband is alive but has damaged his throat and can't speak, she is also asked to identify the attacker who died but he mysteriously looks like her husband and her paranoia becomes apparent as to is dead and who is alive.
If Rutger Hauer didn't put you off picking up hitch-hikers well this episode might, I wouldn't go as far as to this one what a bit of a mind screw but certainly had me on the edge of my seat anyway. Anna Calder-Marshall plays the wife who thinks she has brought a killer home and her husband is dead, she does give a great performance as whether she is paranoid or not and do doppelgangers actually exist.
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