The Fortieth Door (1924)

Plenty of adventure in the desert with "villains dashing madly across deserts with the lives of both the hero and the heroine at stake, - long underground avenues, trick doors, trap doors, and many ways of the unruly villains to torture the innocent. Allene Ray plays the daughter of a Mohammedan desert merchant, and the discovery that she is really French furthers her romance with the hero. Also featured are archaeological diggings and rescue by the British Army." (Variety-1924)