L'Atlantide(1972)

Two young French officers get lost in the Sahara desert and find themselves prisoners of Antinéa, who rules over the lost city of Atlantis. Under her evil influence, one of them, blinded by his love for her, loses his mind and goes so far as to murder his comrade... Jean Kerchbron adapts Pierre Benoît's book for this film, which is more concerned with social reflection than fantasy.