A whispered warning, rumors of a dognapping ring, a mysterious red van with Jersey plates--all chill the nine-year-old Garcia twins, Elena and Michael, when their beloved dog Perro disappears from their brownstone neighborhood. Soon they are joining forces with Bonnie Balsam, a roller-disco rock star whose peach-colored poodle Madame Bovary is snatched from Bonnie's grasp. Bonnie offers a $1,000 reward for both dogs, and teenage Hector, a neighborhood baddie between jail terms, responds; but then Elena, spotting and investigating the van, finds herself transported to a nearby island and locked up on a boat with a lot of stolen dogs. (Do they plan to drown her? It seems so.) Even after Elena and Madame Bovary are rescued (Michael plays a major role in tracking the van), it seems that Perro is lost forever--but wait. ""If you think so, you can stop reading right now. But if you have a little faith, a little heart, keep on to The Last Word. . ."" wherein Perro is found, Hector and the other dognappers are jailed, and Bonnie soars to the top of the charts, with Madame Bovary on her record jackets. Among the current flood of easy, dotted-line mysteries, this is competently plotted and lightly flavored, with an extra measure of heart.