YOU'LL NEVER GUESS THE END

Wersba, who usually takes on teenage angst with a fair blend of honesty and high comedy, nearly steals her own show with a subplot that spoofs the ``literati'' of the adult book world. Joel's older brother, JJ Greenberg, has achieved Jay McInerney- like fame with his first book and is making the rounds of talk shows with other writers, like Jennie Tamowitz (from whom he seems to have borrowed some very Slaves of New York-style observations). Joel suffers through the (he believes) unearned admiration—at least until JJ's ex-girlfriend, daughter of a Trump-like real estate tycoon, is kidnapped. Then Joel goes into action, unearthing both the kidnappers and Marilyn with the help of his trusty bloodhound Sherlock. Light on plot, heavy on humor and dramatics, and likely to please Wersba's fans everywhere- -especially those who have access to the ``inside'' jokes. (Fiction. 12+)