The year is 1917, the third year of the World War. Many people are stricken with poverty and hunger. Karel, the eldest son of the bricklayer Svetlan has been called up to the front and his mother exchanges his coat for a bag of rotting potatoes to help feed her two younger sons - Rudla and Ládík. Her boys are playing with four other children from their Plzen suburb on an army training ground. They try to make soup out of a deadly wounded crow they have found, but they first have to wrestle the bird from a competing group from Skvrnany. They make a solemn promise on the crow's feather and become a gang.
—NFA.cz