An English country home during a house party becomes the scene of a double mystery. One of the three detectives employed on the case is a woman whose common sense, calm, and plain logic are skillfully employed in straightening the tangle. - NY Times Book Review, Aug 16, 1914.

Mark Brandon, a writer from Australia is in England to visit an old friend, Sir Quenton Rotherdene. However, while walking across the Downs on his way there, he sees a mysterious woman and then finds a murder victim with a moonflower clasped in his hand. More mysterious happenings, shocks and surprises ensue! - Summary by J M Smallheer