Deep below the earth, we spend three days with the men and women working at the frontline to keep Russia, and the world, fuelled.
Two men died but miraculously more than 100 reach the surface safely.
A methane explosion ripped through the pit in Kemerovo region - but 101 safely escaped to the surface.
A methane explosion at Mine No. 7 in the Prokopyevsky district of Kemerovo region led to the deaths of four miners.