The Twentieth Door is a thrilling adventure novel written by Charles M. Sheldon. The story revolves around a young American archaeologist named Tom Jordan, who sets out on a quest to find a lost city in the Sahara Desert. Along with his friend, a French archaeologist named Marcel Brissac, Tom embarks on a dangerous journey through the treacherous terrain of the Sahara in search of the lost city.As they journey deeper into the desert, Tom and Marcel...