B Movie Shown With 'Jaws' in 70's: Old Lady Kills in Traffic

by Matt
(Portsmouth, England)

Anyone remember the name of a film that was shown in cinemas in the UK immediately before Jaws was screened - this was in the days when cinemas showed 2 films in one screening - a short movie before the main event.

A man picks up an old woman to give her a lift in his car. When the car stops at a set of traffic lights she takes out a knife or sickle of some description, and kills him.

The film ends with her getting out of the car whilst it remains stationary at the lights. I can't remember if she does this more than once in the film or not - I think someone has a lucky escape at some point but it's so long ago I can remember no more than this.

Any clues?