Basia and Stefan are a young married couple during World War II who risk their lives to bring aid to Jews. He is an architect, she a nurse - a member of "Zegota" (the Polish underground organization to aide Jews in occupied Poland which operated under the auspices of the Polish government in exile). The series takes place both during the war and in the present day. Basia and Stefan meet accidentally, fall in love and soon marry. Basia is active with the underground from the beginning of the war. Stefan is not but his attitude changes due to a family tragedy.