The valley of ghosts

The Valley of Ghosts is a crime novel by the British writer Edgar Wallace which was first published in 1922. The novel was originally serialised in The Popular Magazine, Jul 20-Sep 7, 1922, in four installments, and the first UK book edition was by Odhams Ltd., in London, in 1922. Small, Maynard & Company published the first US book edition, in New York, in 1923. (This summary is from Wikipedia.)