Assignment II: The Railway Station (1) (S02E01)

Sapphire and Steel step into an eerie, deserted railway station where ghostly presences linger. George Tully, a paranormal investigator, has been monitoring the site for weeks, hoping to communicate with the spirit of a young man who is frequently heard whistling through the corridors. The duo allows Tully to assist them in their inquiry, but Steel cautions him that this apparition poses a threat far beyond that of a mere ghost.