The year is 1820. The landscape of England is undergoing sweeping change as the country pioneers the steam-driven machine age. The Morlands, too, face change: Cousin Africa returns from St Helena to startle society with her unconventional ideas, and Lucy brings her sons home from their Grand Tour, brimming with ideas for their future. In Manchester, Sophie and Jasper meet fierce opposition to their plans for re-housing the factory hands, while in London, Rosamund enters a bizarre agreement with her husband Marcus, with bitter consequences.

And at Morland Place, James and Heloise watch their two sons approaching manhood. Benedict delights equally in love and locomotives, while Nicholas, the heir, develops a taste for more unusual pleasures - and an impatience to claim his inheritance.