Prune the frills of its finer plot points, and local author Alyson Foster’s debut novel might appear a tad mundane. The wife and husband nested in the novel’s center embody a relationship problem best recognized in cliché: Professor Jess is down-to-earth, feet rooted firmly to the ground, while her husband Liam’s a stargazing space case. It’s a tagline that could easily adorn the cover of an impulse buy at the grocery store checkout line.

For Jess and Liam, the cliché does ring true—but mostly in a literal sense. Jess is a botanist, see, and Liam’s an astronautical engineer. Their marriage is as muddied by spaceship issues—the tragic launch-site explosion that Liam’s commercial space travel company has to rectify—as it is by mismatch and extramarital intrigue, though there’s plenty of that, too. In other words, it’s less Cosmo, more Cosmos: A Spacetime Odyssey.

The action unfolds in a series of emails, each chapter a new message sent from Jess to her colleague Arthur, who’s off on a research project in the subarctic. She tells Arthur of the backyard greenhouse she’s building, the reporters she’s evading, the filmmaker who’s hoping to follow her family’s reaction to the accident. Arthur tells her, well, nothing—at least from the reader’s view. All that’s seen of the email thread is Jess’ side of the conversation. What’s left becomes a monologue, broken into bite-sized pieces and headlined helpfully to mark the story’s path.

The format’s a unique vehicle for telling a story, and Foster’s at her best when she’s pressing its limitations. By omitting half of the book’s defining conversation, Foster digs out an absence at the core of her story, shaping a complex Arthur simply from Jess’ reactions. We may never hear from him, but we know him well from the shadows he casts on Jess. He is the black hole heart of the book, around which its action orbits.

Too bad, then, that Arthur and the complicated intimacy he shares with Jess so frequently get shouldered aside. Increasingly, as Jess grapples with the unspooling sins of her husband’s company, Arthur seems forgotten even as he’s being spoken to. At times he appears to exist only to goad her on to the next plot point. Convenient for Jess, sure, but it reduces a challenging device to a simple gimmick.

Those who surround Jess suffer from much of the same treatment. Most are reduced to a single characteristic—Liam: manic determination; Jess’ young daughter: comedic relief—and used as levers to propel her onward from event to event.

Still, Jess remains compelling, crafted by Foster with wit and sympathy. Foster litters the book with curious details, and told in Jess’ voice, they can swing from funny to beautiful. Jess awakens one morning to find that the CNN vans tailing her are actually tailgating—grilling sausages first, before whipping out their cameras. At another point, observing a table scarred by Liam’s heavy hand while writing, she remarks, “It felt like topography, like the map of a world he was fearlessly making his impression upon.” And, in a peal of laughter heard from afar, Jess hears “a giddy, delighted sound that crackled subtly in the quiet air, like lightning does when it’s forming, when it’s still electrons racing from the clouds to the clods.”

It’s in moments like these that this email thread of a novel finds its energy. Look for them, linger on them, and despite the silence in reply, Foster’s conversation will be worth a listen.

Alyson Foster will appear at Politics and Prose Thursday, July 10, at 7 p.m. 5015 Connecticut Ave. NW. politics-prose.com