THE UNSUITABLE, by Molly Pohlig

 Iseult Wince, 28 and very nearly a spinster, lives in mourning clothes for her mother Beatrice who died giving birth to Iseult. She lives with her cold, preoccupied father, her sole companion the housekeeper. Plus Beatrice, who lives in the swollen scar on Iseult's neck. Despite her age and her peculiar manners, her father does not give up trying to foist her off on various would-be suitors. To date, Iseult  - with her mother's help - has driven them all off.
Beatrice might be gone but she certainly isn't forgotten: She never stops talking. Awake or asleep, Iseult has the drone of her dead mother's voice in her ears, often drowning out the dinner table conversations and often drowning out Iseult's own thoughts.
When her father finally brings s suitor who will take her on, a chain of seemingly minor events is set into motion, culminating in a catastrophic father-daughter interview that changes both Iseult's past and her future.
Creepily atmospheric and at times graphically gruesome, The Unsuitable is also slyly funny. The mother-daughter dynamic is a psychological study in what appears to be disappointed love as well as selfishness and cruelty. The denouement is gothically graphic.
Initially, the format the author chose tempted me to stop reading, but a dozen pages in I couldn't put it down. It's a 5, a finely-drawn psychological map of madness, normalcy, cruelty and -  maybe - demonic possession.
Thanks to NetGalley and MacMillan Publishing for supplying an advance copy. The book will be issued in March 2020.