"When Slade McGinty accepted Konrad Geltwald's commission he had no illusions about his client. Geltwald lived in terror of El Maestro, a mysterious newcomer to London crime, who backed his threats with death, swiftly and expertly executed. El Maestro was suspected of being the elusive master spy who haunted the dark shadows of international espionage like a sinister phantom. When Geltwald was murdered Slade found himself involved in a deadly race to unmask the master spy before it was too late."