The Fortieth Door is a 1924 American adventure film serial directed by George B. Seitz and starring Allene Ray and Bruce Gordon. The film is considered to be lost. The Library of Congress includes the film among the National Film Preservation Board's updated 2019 list of "7,200 Lost U.S. Silent Feature Films" produced between 1912 and 1929.

Plot

As described in a film magazine review, this desert story concerns Jack Ryder, an American archeologist in Egypt, and Aimee, who is believed to be a Mohammedan. Jack falls in love with Aimee at a dance in a Cairo hotel. Her father agrees to betroth her to a swindling nobleman to keep from being arrested for trading in narcotics. In the ruins of the Egyptian tombs, Jack finds proof that Aimee is a young French woman whose parents had been captured by bandits and had then fallen into the hands of an Egyptian nobleman. All ends well, however, and everyone lives happily thereafter.