A young woman has a new position - but will she listen to the voice warning her not to cross the threshold of that sinister house...

Nora Deane, a young nurse, has been instructed to report to 12 Askew Avenue, Charlbury, to look after a new patient. As she steps from the station into an impenetrable blanket of fog, she is glad to accept the escort of a mysterious young man to the address.

Once alone in the darkness, she presses the bell and waits. She shivers. She wants to be inside, out of the dangers of the dark. Yet some inner voice persistently warns her not to cross the threshold of that sinister house . . .