The Gaut tribe lives in a forest belt and does not suspect that very close by, in the steppe, a great migration of nomadic tribes is taking place. Only a miracle saves them from destruction by steppe newcomers. Blacksmith Stig finds two children with unusual appearance in the forest. The girl is too small and cannot tell anything about herself, and the boy stubbornly remains silent. The tribesmen wonder for a long time and come to the conclusion that the wonderful children were sent to Stig by the patron of blacksmiths - the spirit of the earth Fiilmarnen.