Embracing an improbable stretch of sobriety, unlicensed P.I. Duck Darley has proven himself stronger than the temptations that loom in the shadows of New York City. But the familiar pull of self-destruction lingers like garbage in July when Layla Soto, a sharp-tongued Park Avenue teenager with a family as screwed up as his own, presents a twisted missing-persons case he can't refuse . . . Layla saw video evidence of her billionaire father being abducted...