During World War II, he created the character of Dr. Stanislaus Alexander Palfrey, a British secret service agent, who forms Z5, a secret underground group that owes its allegiance to the Allies. The first novel of the Dr. Palfrey 34-book series was Traitor's Doom, published in 1942 by John Long Ltd., while the last was The Whirlwind in 1979.
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