In this tale of espionage set during World War I Britain, we encounter a variety of characters. Surgeon-Major General Hugh Thomson, the works apparent antagonist, who is endeavoring to clear the British troops of spies.
He is on the trail of a German master spy who seems to be able to travel across the lines and back and forth between Germany and England. Captain Granet is a wounded war hero recently awarded the DSO and recovering after having been captured twice and escaping twice from the Germans.
