Spies Ltd.

Part 1, Spies Ltd.
Somewhere in London was the man whose criminal genius threatened the safety of millions. Britain's Secret Service knew it, and yet were helpless to track him down, powerless to smash his staggering plot-until a dead man yielded the vital clue that led them step by perilous step to the heart of that ruthless organisation known as-Spies Ltd.

Part 2, The Mystery of Plan 'B6'
Spies Ltd., guided by the cunning hand of Dario Pless, master spy, again stir up a seething cauldron of plotting and intrigue. The War Office's most vital secret is in danger-and its safety depends on the daring and swift action of one man.

Part 3, Spies in Singapore
Spies Ltd., feared by every nation, threaten Britain's safety in the Far East in this thrilling New Novel : : : : : :
From Detective Weekly 1935 England.