Supernatural
2 July 1977, BBC
Role: Mr. Nightingale

Video clip (courtesy of Christina)

The series took an anthology format, where individuals hoping to join the "Club Of The Damned" would be required to tell a horror story, and their application for membership would be judged on how frightening the story was. -- Wikipedia

In this episode, the quiet and retiring Mr. Nightingale is being haunted by an evil doppelganger who has already forced him to murder a young woman. But is he really being haunted, or is he just mad?

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