In 1943, Lvov, Poland was a beautiful city held in the iron grip of the Nazi occupation. The weak prey upon the weaker; the poor steal from the less poor. Near the bottom of this chain is Leopold Socha, a petty thief. His knowledge of the sewers' intricate maze of tunnels and chambers, in which he hides his loot, has earned him a menial job as a sewer worker. But there is a group of people in Lvov worse off than Socha - the Jews. Crowded into a ghetto, they are being worked and starved to death. Realizing that the ghetto is about to be destroyed, a motley group led by Mundek a young man determined to survive the war, they plan in secret to plot an escape into the sewers. Under constant surveillance, they manage to tunnel down. As soon as they enter this dark netherworld, they are discovered by Socha. The Jews offer him money to hide them. The consequences of aiding Jews would be public hanging of the helper and his entire family. But Socha desperately needs this money. In spite of grave misgivings on both sides, they strike a deal. As the Nazis start to liquidate the Lvov ghetto, Socha seizes the opportunity to profit by keeping them hidden and protected them from the devastation above. As the pressure to betray the Jewish families builds, Socha finds himself increasingly in danger, and abandons them to protect himself. But fate and his growing respect for Mundek and an awakened conscience drive him back, and he commits himself to protecting his new "family" at all costs. Socha now risks his own life and that of his family to try and save a dozen people from certain death by hiding them in the sewers. But an old acquaintance of his who has recently been promoted to local commander working for the Germans, grows suspicious of Soha and has new information from informants that people could be hiding in labyrinth of sewers under the city. Is their time running out? An incredible true story of courage from WWII.