If you’re fascinated by unexplained phenomena, hop in a beat-up Audi with the kooky and supersmart Cassie Klein and her dog Luna for a voyage of discovery involving a giant moth, a West Virginia bridge collapse and a hot cryptozoologist. The droll Ms. Coll strikes again!

It’s safe to say Washington is one of the better-documented cities on Earth. Last year alone, the roster of books set in and around here included headline-snagging national bestsellers (Michael Wolff’s devastating account of the Trump-era capital, which sold 1.7 million copies in three weeks) as well as slightly less buzzy works (George Mason professor Dae Young Kim’s study of how information technology affects the region’s Korean immigrants, which almost certainly did not sell 1.7 million copies).

A writing professor haunted by mysteries in her past—and by moths, bridges, unfinished student stories, and her husband’s lover’s nightguard—returns to the scene of her parents’ deaths.