The Cossacks have always been cavalier with safety in their mines, believing it manly to take risks. But when a score of Cossack miners are trapped underground, it falls to the Welsh miners to save them – at a cost. The Tsar rewards the bravery of the rescuers with gold medals, but when John, Glyn, Richard, Alexei, and the women travel to St Petersburg, both Sarah and Glyn's Cossack mistress Praskovia remain in Hughesovka to help nurse the victims of an epidemic of typhoid that began in the pit houses.

But Sarah has another reason for remaining.

While the men are away, Sarah leaves Hughesovka forever, carrying a secret that has driven her from the first real home she has ever known and the only friends she has.

Meanwhile, unbeknown to the immigrants, Richard's first love, Alice, and Glyn's estranged wife, Betty, are travelling the long miles to Hughesovka, along with Richard and Anna's younger brothers. But what will chapel-going Betty, who has a surprise of her own for Glyn, make of Glyn's exotic, Titian-haired housekeeper who is soon to become the mother of his child?