Ambrose Lavendale, Diplomat

Mr Ambrose Lavendale. a young English-American diplomat, leaves the Embassy service to work as a secret agent in London during World War One. He meets Mlle. Suzanne de Frayne, who is similarly employed by the French, while he is shadowing a scientist who has developed a formula for a lethal gas explosive. In a series of connected stories, the pair uncover German spies, foil plots to divert munitions from the Allies, steal secret weapons, and fall in love.