Five to Five by D. Erskine Muir
When wealthy elderly Simon Ewing is found murdered in his flat, it appears to be a robbery gone wrong. Two rings were taken from the dead man's hands, but his hidden jewelery strongbox remained untouched, except for one missing diamond solitaire. An unknown man was spotted exiting the building; there is evidence that he had searched the upper floors before attacking Ewing when the old man was briefly left unattended. But how could an outsider have known when to strike? And why take only one ring from a treasure trove? Superintendent Woods is called in, and through patient careful detection begins slowly to disentangle the clues, as suspicion shifts from one character to the next. This classic detective novel from the 1930s is now republished for the first time.