Usually, crime writers who give birth to protagonists deserving of future series want to feature those characters as prominently as possible in subsequent installments. Not so Boris Akunin, who succeeds his celebrated first novel about daring 19th-century Russian sleuth Erast Fandorin, The Winter Queen, with the less inventive Murder on the Leviathan, in which the now former Moscow investigator competes for center stage with a swell-headed French police commissioner, a crafty adventuress boasting more than her fair share of aliases, and a luxurious steamship that appears fated for deliberate destruction in the Indian Ocean. Following the 1878 murders of British aristocrat Lord Littleby and his servants on Paris"s fashionable Rue de Grenelle, Gustave Gauche, "Investigator for Especially Important Crimes," boards the double-engined, six-masted Leviathan on its maiden voyage from England to India. He"s on the lookout for first-class passengers missing their specially made gold whale badges--one of which Littleby had yanked from his attacker before he died. However, this trap fails: several travelers are badgeless, and still others make equally good candidates for Littleby"s slayer, including a demented baronet, a dubious Japanese army officer, a pregnant and loquacious Swiss banker"s wife, and a suave Russian diplomat headed for Japan. That last is of course Fandorin, still recovering two years later from the events related in The Winter Queen. Like a lesser Hercule Poirot, "papa" Gauche grills these suspects, all of whom harbor secrets, and occasionally lays blame for Paris"s "crime of the century" before one or another of them--only to have the hyper-perceptive Fandorin deflate his arguments. It takes many leagues of ocean, several more deaths, and a superfluity of overlong recollections by the shipmates before a solution to this twisted case emerges from the facts of Littleby"s killing and the concurrent theft of a valuable Indian artifact from his mansion. Like the best Golden Age nautical mysteries, Murder on the Leviathan finds its drama in the escalating tensions between a small circle of too-tight-quartered passengers, and draws its humor from their over-mannered behavior and individual eccentricities. Trouble is, Akunin (the pseudonym of Russian philologist Grigory Chkhartishvili) doesn"t exceed expectations of what can be done within those traditions. --J. Kingston Pierce