Rachel and Malrich are the sons of a German father and an Algerian mother. Born in a small village in the Algerian hinterland, they are sent to Paris to be educated. Rachel excels under the French education system to become a successful businessman working for a multinational, but Malrich, 15 years younger, grows up in the banlieue, drops out of school and mixes with the wrong crowd. The brothers keep a wary distance from each other until the day their parents are killed in an Islamic fundamentalist raid. When their father's personal effects reach Paris, Rachel discovers that Hans Schiller was a reputed chemist before the war, who joined the Nazi party and then the Waffen SS. Posted to Auschwitz, he played an active part in the extermination of thousands of people. At the end of the war, he escaped to Egypt.
There Nasser lent him to the burgeoning Algerian FLN, and after Independence, he settled in Ain Deb, where he started a family, enjoying the respect given to the mujahideen Rachel feels compelled to re-examine his heritage and so begins a journey full of foreboding back to Algeria, then on to Germany to trace his father's past and to attempt to come to terms with the Shoah, one of the great taboos of Muslim culture. The attempt proves more than Rachel can bear, and it is left to the streetwise Malrich to take up the trail and complete his brother's unfinished business.