A San Francisco doctor hunts for a family’s DNA in this novel.

Dr. Pierro Cognetto’s oldest patient, Howard Hugh, fascinates him. Though nearly 103 years old, Howard looks decades younger and is rarely sick. Pierro has seen Howard’s brothers as well—all surprisingly healthy, century-old men. Convinced there’s a secret, which he dubs The Hugh Factor, Pierro investigates. This entails collecting the DNA of the Hugh brothers, who live across the United States, including in Texas and Ohio. Of course, his actions are illegal, since he’s not asking permission, so Pierro occasionally disguises himself as a woman to stay anonymous. In the course of his investigation, he hires escort Cleopatra Wesson. Unexpectedly, the 80-something single virgin finds love and a new sexual appetite while still covertly gathering DNA. Back in San Francisco, Pierro’s concerned neighbor calls the police; the reliable doctor, who’s run an office for more than 50 years, has seemingly vanished. One investigating cop, based on Pierro’s apparently suspicious credit-card activity, is certain the physician is “up to something.” He sends an officer to track Pierro around the country to find any evidence of wrongdoing. Emm’s tale is more diverting than suspenseful. For example, Pierro is a tranquil lawbreaker, and his most complex crime is an amusing “DNA heist.” The police, who lose track of him more than once, surmise that a mole in the department is aiding the doctor. Straightforward prose fosters a smooth narrative despite lingering on mundane tasks, such as ordering food and checking into hotels. Meanwhile, romance between the amiable characters Pierro and Cleopatra is certainly welcome. Unfortunately, Pierro spends too much time ogling Cleopatra’s physical attributes, complete with tacky descriptions, such as equating her breasts with “gigantic mountains.” This all culminates in an ending that, while memorable, lacks resolution.

A breezy, enjoyable tale of a physician’s escapades, despite a few stumbles.