When a psychological thriller by a debut Nigerian writer hits U.S. shores, you have to stop and revel in its novelty among the growing number of more literary books by African writers. Set in an upper-middle-class neighborhood in Lagos, Oyinkan Braithwaite's "My Sister, the Serial Killer" is a showstopper in many ways — a no-nonsense one with a wicked sense of humor.

Here is a novel that shrugs off the oft published themes of poverty, political turmoil or civil strife on the African continent. Rather, it concerns itself mainly with the comfy lives of two sisters, Korede and Ayoola, one of whom is undeniably gorgeous and has a pesky habit of killing her boyfriends.

When the novel opens, Ayoola has just killed her latest boyfriend, Femi — and Korede, the sole narrator, declares, "Femi makes three, you know. Three, and they label you a serial killer." As it turns out, Korede, a nurse by profession, is also the type of resourceful sister who sweeps in, cleans up the scene and helps her sister dispose of the body. Thorough and disciplined, Korede becomes complicit in not only covering up Ayoola's crimes, but also in making sure they both evade punishment.

But from here on, as cleverly as the narrative unfolds, it relies too heavily on the all too familiar tropes of morality tales. Korede, the "ugly" one, returns to work at the hospital with hawklike diligence, and layabout Ayoola, a total babe and magnet for men, has no problems outsmarting the police or dating again. Also, an attractive doctor with whom Korede is hopelessly infatuated unleashes chaos when he falls in love with the irresistible yet dangerous Ayoola instead. Men — they just don't make out well in the novel unless they happen to be trapped inside bodies as comatose patients or, worse yet, dead.

Along with Braithwaite's terse and efficient prose, the novel's uniqueness hinges on the nuances in the relationship between the two sisters. Sisterhood is complicated; it can be hard work. That Korede feels this deep sense of responsibility for Ayoola's well-being is heroic, even though it may seem patronizing at times.

An abusive, philandering father appears in flashbacks interwoven with some skill and dread into the narrative, and here Braithwaite prods at the hornet's nest of patriarchy that can sometimes plague families in Nigeria. However much you might have wanted Braithwaite to, metaphorically speaking, kick that darned nest, this is a book to be enjoyed on its own terms. Take it or leave it — that's exactly how Korede, the smart and straight-shooting narrator, prefers it.

My Sister, the Serial Killer, by Oyinkan Braithwaite

Angela Ajayi is a Minneapolis-based book critic and award-winning fiction writer.

My Sister, the Serial Killer
By: Oyinkan Braithwaite.
Publisher: Doubleday, 226 pages, $22.95.