Whistle And I'll Come To You - 1968 UK TV Ghost Story

Professor Parkins (Michael Hordern) has come for a week's holiday in a small hotel on the Norfolk coast. Wandering in a clifftop cemetery he discovers a bone poking out of one of the graves and takes it back to the hotel in order to examine it. He soon realises that the bone has been carved into a whistle, and can't resist raising it to his lips and giving it a blow, an act which has eerie and unexpected consequences....