John Fay's drama set in the 19th century, based on the history of Quarry Bank Mill in Cheshire. Children as young as nine work 12-hour shifts at the factory and the new class of mill-owning families are prospering, but the so-called white slaves of England are about to take their lives into their own hands as outsiders with new ideas enter their world. The ruthless overseer forces apprentice Miriam to leave the shop floor with him against her will, and his absence leads to a serious accident.