Igna­cy Chiger (1906−1975), a resource­ful Jew­ish busi­ness­man who defied the odds in Nazi-occu­pied Poland, mas­ter­mind­ing a high-stakes plan to save his fam­i­ly by van­ish­ing into the sew­ers of Lvov, where they sur­vived in dark­ness for over a year.