Schoolteacher Rosy Winter is dying.

Her husband Charlie offers all the relief he can. Rosy's sister-in-law, Sally, offers none.

But Rosy feels something growing in her. A hard knot in her chest.

Beyond the homeopathic remedies, the dinner party obligations, the snatched whispers on wards and in staffrooms, a force - murderous, feminine, feverish - is stirring within her...