Guy Martin works on a machine that can be credited with helping to kick-start the Industrial Revolution. Joining a team from the Black Country Living Museum, he helps to restore a Newcomen engine - an 18th-century steam-powered device used principally to pump water out of mines. As the rotting timber structure is replaced, worn parts repaired, the boiler cleaned and crumbling brickwork rebuilt, the presenter also learns about the lives of the men, women and children who mined coal