The Secret In Harley Street
Written by
Gilbert Frankau
Copyright 1933
Story 1 of 7 in The Seven Secrets of Marcus Orlando series, published in The Story-teller, December 1933. Reprinted as part of the anthology A Century of Spy Stories edited by Dennis Wheatley, 1938. Reprinted in , a collection of espionage stories by Frankau, 1934.
Marcus Orlando is exercising his new horse around a London park when he spots an infamous agent for the Soviet Union attending a Bolshevik rally. Orlando knows the man, a former British physician struck down from practicing, is in the country for no good reason and Orlando wants to know what that is.