Laura Lippman's latest isn't a whodunit or whydunit but more of a whendunit.

Throughout "Prom Mom," the writer of "Every Secret Thing" and "Sunburn" creates suspense around our vague notion that something bad is about to happen, even if we're not sure what it is or when it will occur. She alternates between the points of view of three characters: Amber, who became infamous for killing her newborn while at her high school prom but, decades later, returns to her native Baltimore to open an art gallery; Joe, her prom date and father of the baby, now a successful Baltimore Realtor; and Meredith, Joe's wife, a bougie plastic surgeon.

From the get-go, it's clear these characters are in conflict, with one additional complication: Joe is having an affair with a significantly younger woman who may be obsessed with him. There are hints that we don't know everything about the fateful prom in 1997. And, because Lippman is quite specific about the dates when the book's events unfold — late 2019 and early 2020 — it's clear the COVID-19 pandemic will play into whatever it is the three main characters are up to.

"Prom Mom" is absorbing and the 1997 event anchors it in an unimaginable tragedy that we know has occurred in real life. But that "whatever it is" is an issue. While we're learning the intriguing specifics of Amber's gallery, which sells art created by incarcerated people, and watching Joe's deal to acquire a mall at probably the worst time in history to acquire a mall, Lippman interests us in what they're doing. But there isn't a lot happening in "Prom Mom." In fact, the book jacket gives away something that seems like it will drive the plot of the thriller but that doesn't happen until page 269 of the novel's 302 pages. (My advice: Don't read the back of the jacket.)

There's a method to what seems to be Lippman's madness. By the end of "Prom Mom," we understand what she's doing, why she's chosen a title that defines her main character with events she's trying to surmount and how people who are underestimated can exploit that underestimation.

That's something Lippman, whose characters tend to be smart, underestimated women, often writes about. It's satisfying territory but Lippman has explored it better — with more compelling protagonists — than she does in "Prom Mom."

Prom Mom

By: Laura Lippman.

Publisher: William Morrow, 302 pages, $30.