Primo Levi wrote an essay he called "The Gray Zone". It explores a particular spectrum of Holocaust-era figures who defy the categories that help to sort, define and make more comprehensible the events and experiences of the Holocaust. He mentions those people who made small to great compromises with the German authorities to obtain some advantage: protection, larger ration of food, a prolongation of life. They were members of the Jewish councils and they formed the 'Sonderkommandos': the prisoners who shepherded victims to the gas chambers