The sentences in Craig Welch's Shell Games: Rogues, Smugglers, and the Hunt for Nature's Bounty (William Morrow, $26) are not particularly elegant. But they don't need to be: Welch, a crack reporter and chief environmental writer for The Seattle Times, turns out a true-life shellfish caper, centered on the efforts of Washington Department of Fish and Wildlife detectives to lock up the West Coast's largest poacher of geoducksoutsize, phallic-looking clams that fetch top coin on the Asian market. The book is full of characters Raymond Chandler would have conjured, if Chandler had been a shellfish nut: crooks named Slim and Spook, detectives scouring Puget Sound in a vessel called Clamdestine, and an informant turned geoduck kingpin with a whalebone necklace and a talent for carving elaborate totem poles. The prose occasionally delves into the stuff of hackneyed mysteries"Chasing Tobin [the kingpin] would be like grabbing at smoke," Welch writesbut, then, the cops-and-robbers nature of the story makes you want to read the whole book in one gulp. That's a good thing, since page-turning mysteries that make you think are a rarity. It would be impossible to read Shell Games and not come away with a fresh, considered perspective on your next order of clams.