The long subtitle—``A Counting Story in Reverse (A Tale of Wickedness—and Worse!)''—explains it all: Ten toothy fuchsia piranhas (``Each a slippery schemer, with a dozen dirty tricks'') ogle and menace and, one by one, devour each other; the last is snapped up by a crocodile. The violence here is considerable, but tastefully implicit; the beady-eyed Amazonians in Chess's brightly tropical river scenes (intriguingly displayed in over/under cross sections) simply disappear, while the author also leaves their gruesome demises to the imagination. Wise's rhymed verse has a catchy rhythmical beat that propels it as persistently as the predatory fishes' hunger. Readers of a certain sort will relish this mightily. (Picture book. 5-8)