A school trip becomes a nightmare for young Jon Jones when he is trapped unconscious underground, and emerges to find himself in the hellish conditions of a long disappeared Welsh mining community.Can Jon retain his sanity when he believes he has lived with people who died a hundred years ago?Based on fact, this is the story of tragedy, cruelty and ultimately heroism in a Welsh coal mine in the 1920's and the fight by one man to preserve the memory of the miners who died in an underground accident.