In the night between the 12th and the 13th of December of 1943, Primo Levi was arrested in Amay (Valle d’Aosta) during a fascist military operation to search for partisans. In the same night, Luciana Nissim, Vanda Maestro, Aldo Piacenza and Guido Bachi were also arrested: in the previous weeks, they had been gathering in a small rebel group that was linked to Giustizia e Libertà. Despite the fact that this meaningful episode marked the beginning of his long and painful journey to Auschwitz as a deported Jew, Primo Levi did not like to talk about his experience as a partisan hidden in the mountains. On the contrary, he later defined it as “the darkest period” of his career: “it is a story of young people with good intentions that behaved incompetently and stupidly, and needs to be forgotten”, he wrote. What is the reason that lies behind this severe judgment and Levi’s unwillingness to discuss it, other than a short novel and some references in his literary and historical works? Might it be “the nasty secret” that obscured the minds and hearts of all the members of the partisan cell? “The very same secret - Levi says - that had put us in danger of imprisonment, killing, a few days earlier, our desire to resist and to live”? The brutal execution of two young members of the cell whom, with their actions, had threatened the group’s safety and existence might certainly be the cause. Nonetheless, reading the precise and documented report of the weeks when Levi decided to transform his antifascist stand into a partisan struggle helps us to better understand his life, creating a link between his partisan experience and his fight for survival in the Auschwitz concentration camp.