A Russian family, escaping religious persecution by the Bolsheviks, escaped to the remote forests of the Russian Far East. They lived there for over 40 years, cut off completely from the rest of humanity until they were found by a group of Soviet geologists.

Noteworthy quote:

The low door creaked, and the figure of a very old man emerged into the light of day, straight out of a fairy tale. Barefoot. Wearing a patched and repatched shirt made of sacking. He wore trousers of the same material, also in patches, and had an uncombed beard. His hair was disheveled. He looked frightened and was very attentive…. We had to say something, so I began: ‘Greetings, grandfather! We’ve come to visit!’
The old man did not reply immediately…. Finally, we heard a soft, uncertain voice: ‘Well, since you have traveled this far, you might as well come in.’