Leopold Buczkowski (1905–89) is considered one of the most enigmatic Polish prose writers. Czarny potok (Black Torrent), his first postwar novel and his masterpiece, was critically examined in terms of its complex aesthetic. This article focuses on the thematic of Black Torrent, which centers on the destruction of the Jewish town Szabasowa. Thus, in one sense, the novel serves as a Yizkor Book, a testimonial of the destruction of a Jewish community. In another sense, the novel presents a unique vision of Polish and Jewish underground insurgents on a mission to protect the surviving Jewish children and defend the population at large. This Polish-Jewish band proclaims an empathic-dialogic relationship of equals; their shared goal of fighting the occupier and collaborators supersedes the identifications of ethnicity, blood kinship, or religion. However, unavoidable exposure to the inhumane Weltanschauung of the enemy raises the issue of the effects of the genocidal system on the humanistic orientation of the band members. While attempts to reform the perpetrator in an empathic-dialogic interaction fail, the recourse to a violent, ruthless struggle for survival denotes a compromise of the humanistic values of equality, justice, and empathy. The article shows how Buczkowski’s ars poetica informed by his humanistic-enlightened upbringing enabled his vision of human solidarity and mutual obligation under the circumstances of genocidal terror.