Triangle of Fear — John Newton Chance

A man is running away, but no one follows him. He runs to a hiding place he knew as a child, but it is crumbling, day by day. He finds there a man and a woman, pretending to be housekeepers. Who are they? Murderers, traitors, spies? Then suddenly he realises that they too are waiting to escape. From what? There is no one to be seen, yet slowly the shadow of death creeps in. They watch each other, wondering who must meet death first...