Written by Gilbert Frankau
Copyright 1934
A collection of 13 short stories previously published in The Strand or The Story-teller and all dealing with espionage in one form or another. The final seven in this anthology all deal with Marcus Orlando. They are:The Secret in Harley StreetThe Secret at Sainte Marie Sur MerThe Secret in the Citronen GasschenThe Secret in the SlumsThe Secret in the SteppesThe Secret in the SuburbThe Secret of His Sire