I am trying to identify the title of a film I saw once on UK TV in the early 1980's.   It was spanish or italian (i think) subtitled or dubbed into english.  The plot is set around a small village cinema one summer afternoon around the matinee performance.  It follows the people going in to watch an american cowboy film.  The twist is that when the "baddie" shoots on the screen, someone in the audience is shot dead.  The police are called, believing murderer to still be in the cinema they replay the film and at the same place, another shot rings out and a further death occurs.  Lastly the inspector runs the film with everybody in the foyer; this time at the critical moment, the character on the screen draws his gun, takes a bead, but doesn't fire as before.  He looks towards the inspector and shoots at him.   In the resulting gunfight the "real" inspector shoots the "baddie" on the screen and kills him - the End.

I've been trying to track this film down for about 10 years.   Can anybody help.  PLEASE ! ! ! 

Thanks

Charles