For the Bielski brothers -- Tuvia (DANIEL CRAIG), Zus (LIEV SCHREIBER), Asael (JAMIE BELL) and Aron (GEORGE MacKAY) -- the woods of their Belorussian homeland have always offered them protection from those after them. Their experience hiding there comes to good use when the Nazis and their sympathizers and helpers, such as a local police officer, start rounding up and killing Jews, including the brothers' father and others on their farm.
While Zus would rather their rebel contingent simply consist of just them, Tuvia knows they must help others, and soon they're joined by a growing number of refugees, such as older school teacher Shimon (ALLAN CORDUNER) and intellectual Isaac (MARK FEURSTEIN), who help them build a settlement in the woods.
With time passing and their wives dead, Zus develops an interest in Bella (IBEN HJEJLE) and Tuvia does the same with Lilka (ALEXA DAVALOS), while young bachelor Asael finds himself falling for Chaya (MIA WASIKOWSKA). Yet, Tuvia must also contend with challenges to his unofficial leadership of the settlement, not only from the likes of Arkady (SAM SPRUELL), a hunter who starts to get power hungry, but also Zus who thinks they should be off killing Nazis and their associates rather than hiding from them.
Accordingly, he ends up going off with Russian officer Viktor Panchenko (RAVIL ISYANOV) his right-hand man, Gramov (ROLANDAS BORAVSKIS), and other guerilla fighters. As the months wear on and a bitter winter sets in, and facing repeated encounters with German forces, Tuvia does what he can to keep order in the settlement, food in the refugees' bellies, and hope in their hearts that they will survive and prevail.