Walsh’s debut, written from the perspective of a narrator in his 30s remembering his suburban upbringing, reads at once like a homage to and an apology for the mediocrity of his hometown: “When compared to the national averages, Baton Rouge normally ranks around 37th in the top 100 metropolitan areas of America, no matter what you’re measuring. However, we always score well in odd polls. We’re off the chart in mysterious categories like ‘enjoys their neighbours’, ‘had a good weekend’ and ‘hopes their children will stay close’.”

The event that destroys this sleepy idyll occurs on a sweltering summer evening in 1989 when a popular 14-year-old named Lindy Simpson is thrown from her bicycle and raped only yards from her home. No one witnesses the attack and the perpetrator is never brought to justice. But suspicion falls on everyone; not least the nameless narrator, who has been spying on Lindy Simpson since he was 11 years old. He can even provide the precise date on which the obsession started: “The day I fell in love with Lindy Simpson was January 28, 1986. This was also the day that the Space Shuttle Challenger exploded.” His feelings are awakened by the stream of pink vomit Lindy produces as their class witnesses the disaster unfold on television.

Walsh’s book, which was seven years in the writing, is an exercise in southern gothic that includes a pair of genuine southern goths. The narrator shaves the sides of his head in sympathy with Lindy’s obsession with “a band called Bauhaus ... She became thin and, most said, bulimic. Rows of small pimples appeared on her chest. This was a hard thing to watch.”

It’s a strange coincidence that the UK publication should emerge at the same time as Harper Lee’s Go Set a Watchman. Both are memory novels containing recollections of a rape. Both are based on first-hand observation of an insular, southern society steeped in heat and paranoia. There is even a significant episode involving the shooting of a stray dog. But whereas critics are divided over whether Scout makes a successful adult, Walsh seems entirely secure with his narrator’s attempts to justify the actions of his teenage self. The tone is supplicatory and insistent (“hear me out”, “I don’t want to lose you in this confession”, “let me explain”); yet the implied sense of intimacy becomes deeply unsettling: “You must live in Louisiana to understand this. You must hide in our azaleas to tell this.”

The most striking passages arise less from the narrator’s fixation with Lindy in particular than his feelings for Louisiana in general; not least the city’s profound inferiority complex. “When people think of Louisiana they think exclusively of New Orleans. We are OK with that ... The people of New Orleans have been known to wonder what a generic place like Baton Rouge, at its core, has to offer. For a long time, we had a hard time coming up with an answer. But now I can tell you. We have guilt.” The passage introduces a digression on the aftermath of Hurricane Katrina, in which the population of Baton Rouge swelled by 200,000 as it struggled to accommodate the influx of refugees. Such rumination runs the risk of forfeiting the suspense, but it amplifies the book’s themes of lost innocence, the end of childhood and the painful discovery that “the world, after all, is not as simple as football games on fall Saturdays, a bunch of friendly people being friendly”. On this evidence, Walsh’s Baton Rouge is a highly nuanced nowheresville that could match Anne Tyler’s Baltimore. Watch this generally overlooked space.

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