Leah Daniels would be the first to admit that she has way too much time on her hands.

It’s October, and she’s been bored and lonely since the summer, when her husband, Clay, moved her and their 11-year-old twins from pricey Seattle to rural Dearborn, Maine, where he hopes to realize his dream of owning a brewery. Having left behind her cohort of “mommy friends,” Leah fixates on the new-chum potential in Clarissa Gaines, who lives with her husband and kids in the only other completed house on a cul-de-sac that’s been abandoned by the developer. In the few months that Leah has lived in Dearborn, she has found her social overtures spurned by Clarissa and her husband, both of whom teach at nearby Chadwick College, so she resorts to a less traditional route to getting to know the neighbors: she spies on them, “Rear Window”–style, and snoops inside their unlocked house when no one is home.

The fact that Clarissa and her family are black offers Leah added incentive to forge a bond: She’s so plangent with her progressive views that she comes across as something of a parody. “The sight of plastic bags makes me anxious,” she admits when she finally gets some face time with Clarissa as the woman unpacks her groceries from the offending sacks. “Our planet is in dire straits.” Never mind how Leah will react if she learns that Clay had an affair with Chadwick College student Mycah Jones, who seems to have been abducted: What if Leah finds out that her husband doesn’t vote?

The police are using “possible hate crime” to describe what happened to Mycah Jones and her boyfriend, who, like Mycah, is black, and who, according to news reports, was with her and got clobbered with a lacrosse stick when she went missing. Clay wouldn’t disagree with the cops; as he tells the reader, “Trust me when I say that there were many people in town who hated Mycah Jones.” (He’s one of them.) But Clay isn’t his marriage’s only secret keeper. Unbeknownst to him, his wife receives an unsigned letter in the mail that reads, “You mustn’t be so hard on yourself, Leah. You were only a child when it happened.”

As “The Neighbor” unspools in first-person chapters split fairly evenly between Leah and Clay, it uses its share of mystery-novel tropes: the unsigned letter, a diary with juicy entries, even an act of hiding under a bed to evade detection. Definitely not a mystery-novel trope: sex scenes centered on racial power imbalances. In “The Neighbor,” one’s race isn’t a tidy little naturalistic detail; it’s a weapon that can be wielded to manipulate others. This is both a strength and a weakness of the book. To his credit, Joseph Souza seems to be trying to spark a conversation about race. But the way that he has his characters employ ideas about black sexuality seems opportunistic and may make some readers – and not just do-gooder liberals – squirm.

Most readers will stick around to learn the truth about Souza’s characters despite their occasionally plausibility-defying behavior, and the book’s conclusion is gratifyingly macabre. As for Leah’s big secret, it’s less interesting than a rather marvelous smaller one: She routinely passes off prepared foods as homemade. Wait: Leah isn’t strictly organic? Back in Seattle, that would have been a crime.

Nell Beram, coauthor of “Yoko Ono: Collector of Skies,” has recently written for the New York Times Book Review and L’Officiel.