Based on factual events, it unfolds during World War II in the Polish town of Lvov, now part of Ukraine. Mass executions in the Warsaw Ghetto have driven about a dozen Jewish Poles to escape the Nazis by fleeing into the sewer system. They hide in the dank, dark confines of the underground, sharing their quarters with rats and rivers of excrement. 

Their benefactor, of sorts, is city sewer worker Leopold Socha (Robert Wieckiewicz), known to most of his fellow townspeople as Poldek. He is not ideal for the job of humanitarian. A miserable lump whose thievery and greed are matched by his virulent anti-Semitism, Socha agrees to help the Jews solely for money. He stands to get rich from the deal.

But then the inevitable change begins. In the hands of director Agnieszka Holland, who also explored the Holocaust in 1985’s Angry Harvest and 1990’s Europa Europa, Socha’s moral awakening is one of those rare movie transformations that feel organic and seamless. There is no epiphany moment, but rather a trickle of small realizations as the man accepts the humanity of what he calls “his Jews.” Wieckiewicz gives a commanding and subtle portrayal — one of last year’s great performances.

A 2011 Oscar nominee for Best Foreign Language film, In Darkness is often harrowing, but too long for its own good, clocking in at 145 minutes. While it doesn’t reach the mastery of such Holocaust films as Schindler’s List and The Pianist (few pictures do), this searing drama is still worthwhile viewing.