In Vienna, Austria, in 1940, two nine-year-old boys, one Jewish and one Aryan, are classmates and best friends when events of the Nazi occupation draw them even closer together as they fight to survive and escape together.
A little mouse living in the church of an Austrian village assuages his hunger by feasting on the organ bellows and causing the priest and the organist to quickly compose a song for Christmas Eve mass, the now famous "Silent Night, Holy Night.".