Stephanie’s Sunday Book Review Book of the Day: My Sister, the Serial Killer

Stephanie’s Sunday Book Review

Book of the Day: My Sister, the Serial Killer

Author: Oyinkan Braithwaite

Genre: Crime Fiction | Psychological Thriller | Dark Comedy

Rating: ★★★★★ (4.8/5)

Some books grip you with elaborate plots. Others keep you turning the pages because of what they reveal about human nature. Oyinkan Braithwaite’s debut novel, My Sister, the Serial Killer, firmly belongs in the latter category. At just over 200 pages, this book is sharp, unsettling, darkly funny, and psychologically astute. Rather than a conventional whodunit, Braithwaite delivers a masterfully subverted crime thriller concerned with an entirely different question: what do love, loyalty, and family compel us to do?

The novel opens with a deadpan hook that immediately establishes its tone: Korede receives a late-night phone call from her younger sister, Ayoola, informing her that she has killed her boyfriend. There is no panic, no dramatic confession. Instead, Korede instinctively reaches for bleach, rubber gloves, and cleaning supplies.

Set against the bustling, status-conscious backdrop of Lagos, Nigeria, the narrative quickly sets its stakes. Ayoola has a recurring issue: her suitors keep dying “in self-defense.” This time, it’s her boyfriend Femi. Because Korede is a disciplined, hyper-practical nurse, she knows exactly how to handle blood and erase traces of DNA. She packs the body into her trunk, helps dump it in the Lagos lagoon, and scrubs the scene pristine. To the world, Ayoola is a grieving, drop-dead gorgeous angel; to Korede, she is a walking liability.

The true conflict ignites when Ayoola steps into Korede’s hospital workplace and sets her sights on Dr. Tade Otumu—a kind, idealistic doctor whom Korede has secretly loved for months. Instantly blinded by Ayoola’s beauty, Tade falls head over heels, forcing Korede into a harrowing psychological corner. She must decide whether to protect the man she loves by exposing her sister, or remain complicit as Tade unknowingly steps into the crosshairs of a serial killer.

At first glance, the sisters appear to embody opposite ends of a narrative spectrum: the beautiful, manipulative villain and the dutiful, invisible older sister. However, Braithwaite avoids flat stereotypes by giving both women profound emotional complexity.

Through carefully rationed flashbacks, the author builds an intricate study of trauma bonds. We learn of a childhood dominated by a tyrannical, abusive father, where Korede always stood as a human shield between her father’s wrath and her fragile younger sister. Ayoola’s sociopathic tendencies are revealed not as a mere plot device, but as a product of a deeply fractured upbringing. Korede’s ongoing loyalty is exposed as a complex psychological prison: her entire identity is wrapped up in being her sister’s keeper, to the point where love has blurred completely into codependency.

Stylistically, Braithwaite’s writing is remarkably economical. Every sentence is lean and stripped of excess exposition, often laced with a dry, wicked humor that catches the reader off guard. The uncomfortable balance between comedy and horror is one of the novel’s defining achievements; you will find yourself laughing at an observation only to remember that the scene involves the calculated cover-up of a homicide.

Furthermore, the Lagos setting functions as a living character rather than a passive backdrop. Braithwaite captures contemporary Nigerian life with immense authenticity. From the social dynamics of the hospital corridors to the nuances of local culture and language, the setting enriches the text naturally without ever feeling performative. The novel remains unapologetically localized while remaining universally accessible.

My Sister, the Serial Killer is a brilliant exploration of beauty as social currency, exposing how quickly society excuses the flaws of attractive people. More importantly, it challenges readers to look into the mirror and ask where their own moral boundaries lie. How easily can an ordinary person become complicit in extraordinary wrongdoing when the perpetrator is someone they cannot bear to lose?

Would I recommend it? Without hesitation. For anyone seeking a tight, witty, and psychologically profound thriller that favors character depth over cheap spectacles, this is an absolute must-read.

Until next week, Have a good read.