The marabout, Hajji Omanah, is dying. Known throughout the vast deserts of Africa as a hermit and devout follower of Islam, Omanah has been keeping a terrible secret, one that has been plaguing him for years. On his deathbed, he plans to reveal it... to his son. What his son doesn't realize is that he's soon to be caught up in the middle of a vicious feud going back over a generation between two powerful European families. Forced to leave France in disgrace, the embittered Albin Richemonte is determined to avenge himself on Hugo von L wenklau and his entire household. Desperate to escape desert exile, Richemonte concocts a brilliant scheme to cheat the marabout's son of his rightful inheritance, and by doing so rob the L wenklau's of theirs as well. In the meantime, rumours of war between France and Germany abound, leading the Prussian High Command to send Hugo's grandson Richard on a dangerous mission into the heart of the enemy. There, he will find himself face to face with his grandfather's greatest nemesis.