If Henry James had lived in the age of pulp noirs, he might have wound up writing books a little like Susan Choi’s third novel,A Person of Interest­: There’s a murder mystery, a solitary man who walks a lonely road on the way to resolving it, and thickets of commentary about relationships, ambition, religious faith, and intellectual life. In theory that’s an ungainly combination, and Choi’s ripped-from-the-headlines story occasionally grinds against her deeply observed passages about her main character, Lee. But she literally starts with a bang: In the opening pages, a mail bomb kills a hotshot mathematician at a Midwestern university, and Lee, the prof in the next office whose best years are behind him, soon becomes the “person of interest” of the title. Choi scrutinizes Lee nearly as much as the FBI does; a letter from a long-lost adversarial colleague reminds him of his past failures, and soon every stubbed toe, every stray conversation, and every trip to the mailbox dislodges another detail about his roles as a father, husband, and academic. Choi’s paragraphs are heavy, dense, carefully shaped mini-essays, and if you’re occasionally tempted to give the Unabomber-esque plot a shove to hurry up and resolve itself, it’s clear Choi’s building something—her portrait of Lee’s paranoia is so exacting and affecting that it’s worth being patient with. Choi discusses and signs copies of her work at 7 p.m. Monday, Feb. 18, at Politics and Prose, 5015 Connecticut Ave. NW. Free. (202) 364-1919.