Summer 1916. A transport of Russian prisoners of war passes through Brno. The health of Russian officer Ryepkin deteriorates so much that he is taken to an Austrian military hospital. He almost dies and needs a transfusion. The German nurse Mathilda is the only one with the same blood type. However, because she hates everything Slavic, she hesitates to help and the chief physician, MUDr. Šrámek, has to remind her of her human duty.