Francis Stevens is the pen name of Gertrude Barrows Bennett. The Citadel of Fear  was her first and most famous novel, published in 1918. It features a “lost city” in Central America, along the lines of Conan Doyle’s The Lost World. However, where the main threats in Doyle’s adventure were dinosaurs, Stevens’ tale features a lost civilization – the ancient city of Tlapallan – which is inhabited by peoples who still practice human sacrifice and worship the ancient Aztec gods.

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