Marguerite Périgord is locked in the attic of her family home, a towering Chelsea house overlooking the stinking Thames. For company she has a sewing machine, Mrs Beeton’s Book of Household Management and a carrion crow who has come to nest in the rafters. Restless, she spends her waning energies on the fascinations of her own body, memorising Mrs Beeton’s advice and longing for her life outside.

Cécile Périgord has confined her daughter Marguerite for her own good. Cécile is concerned that Marguerite’s engagement to a much older, near-penniless solicitor, will drag the family name – her husband’s name, that is – into disrepute. And for Cécile, who has worked hard at her own betterment, this simply won’t do. Cécile’s life has taught her that no matter how high a woman climbs she can just as readily fall.

Of course, both have their secrets, intentions and histories to hide. As Marguerite’s patience turns into rage, the boundaries of her mind and body start to fray. And neither woman can recognise what the other is becoming.