When young Ian Campbell disappeared it was suspected that he had sold to a foreign government an invaluable process for the synthetic manufacture of gasoline. Lois Brendon, Ian's fiancee, refused to believe it. Her faith led her to risk her life in his vindication. The matter was put into the hands of Scotland Yard and Chief Inspector MacDonald began operations. Against him were ranged the subtlest conspirators of two foreign powers, and the case led him through as absorbingly tangled an international intrigue as has ever been spun in mystery fiction.
Edith Caroline Rivett (who wrote under the pseudonyms E.C.R. Lorac and Carol Carnac, Carol Rivett, Mary le Bourne.) was a British crime writer. She was born in Hendon, Middlesex (now London). She attended the South Hampstead High School, and the Central School of Arts and Crafts in London. She was a member of the Detection Club. She was a very prolific writer, having written forty-eight mysteries under her first pen name, and twenty-three under her second. She was an important author of the Golden Age of Detective Fiction.