Prayer and ingenuity have kept the little convent of St. Winifreda in the fen going for centuries, but now the roof leaks, the bell tower is crumbling and rats have moved in. The Bishop wants to send the sisters to a home, disperse the rest and sell the land as a car park. Sister Boniface, convent correspondent, minibus driver, and beginner shopkeeper, charts the rise and fall of their holy struggle, and with the help of ex-offenders, migrant workers, and multiracial nuns, plans not just to save, but also to renew, restore and revivify the sisterhood.