At the climax of "Shinju"(1994), Laura Joh Rowland's first mystery novel, gallant yoriki (police sergeant) Sano Ichiro rescues the shogun from an assassination plot and earns himself a big promotion. It's a pyrrhic victory leading to what Sano immediately realizes will be a thankless position that risks not only death, but disgrace.

"And what is this prize position that I've achieved," he mutters, "except a chance for more of the same?"

And more of the same is exactly what Rowland has delivered consistently for the past 20 years. In 17 hardcover appearances in a chronology extending from 1689 to 1704, her steadfast Edo Period investigator, his wife Reiko and his loyal retainers have emerged intact from high-level conspiracies and intrigues — the most recent being "The Shogun's Daughter."