The so-called “perfect couple” is a reliable starting point for any horror narrative, and a near-demonic mother-in-law only adds to the chance of success.

Motherthing, the third book and first adult novel from Ainslie Hogarth, gives us the charming union between Abby and Ralph Lamb; they are in love and on the cusp of starting a family. The future would have been bright if the pair weren’t sharing a home with Ralph’s mother, Laura, and enduring the darkness of her moods and the casual cruelty she doles out.

Abby’s traumatic history with her own mother makes her desperate for a healthy connection, so Laura’s rejection is all the more difficult to bear. When Laura violently dies of suicide, her painful omnipresence only seems to grow. Ralph is haunted by the loss of his mother – and by her ghost in the basement – and Abby takes responsibility for the cleanup, determined to pull her husband out of Laura’s mess and misery by any means necessary.

Motherthing leans into (and happily subverts) some familiar yet furtive horror fixtures – the dysfunctional power mother figures can wield, the fear of what children are doomed to repeat, and the familial burdens we carry and pass on. Abby’s abusive backstory is thoughtfully relayed, revealing a love motivated by the intense need to be a better mother than her own. Whether she’s mothering her now-broken husband, the elderly woman at the long-term care home where she works, or the child she dreamily conjures up, Abby is determined to be the benevolent caregiver at any cost – ultimately to her own detriment.

“I promise we won’t fuck it up if you’ll please give us a family,” Abby silently implores in the wake of her mother-in-law’s death and imagines that “we bring the baby home with us, to this house, which is still jungle-warm and filled with Laura’s blood, a real river of gore coursing through the main floor.”

Hogarth has a keen eye for dark humour and a knack for playing with the repulsive, but perhaps her greatest achievement here is the skilled depiction of mental illness as a malevolent force that acts upon the individual. “It’s like being dead, only without peace,” Ralph tells Abby about his depression. “You’re just left with your walking corpse and it’s just as dreadful as any corpse is, but it’s you. You’re the corpse.”

Motherthing is an inventive addition to the realm of domestic horror, offering masterful subtlety and a blood-soaked commentary on the maternal impulse. The narrative’s unique discomfort lies in how admirable Abby’s constancy will feel throughout, until both internal and external forces will push her to a horrific brink. Artfully unspooling the protagonist’s deterioration at a nearly imperceptible pace, Hogarth creates a brutal, bloody conclusion that is equal parts surprising and inevitable.

In the world of Motherthing, love is unconditional devotion, but it’s also devouring. Who exactly is being consumed remains unclear – until, of course, it’s grotesquely literal.