Something strange seemed to be happening in the small town of Brockton, Georgia, during my visit to my grandmother's house. First Rags, a collie. . . could not be found by his owners. . . Then my grandmother's beautiful white Persian cat vanished without a clue. . . then a boy named Joey noticed his little brown chichuahua was gone. Naturally, when these people came to me and asked for my help, I joined in the search for the missing pets."" So goes an excerpt from one of the many drafts of eleven-year-old Damon York's spring vacation English assignment. And no wonder he's having trouble completing the paper, what with all the outlandish false clues and bum steers Glaser gives in this illogical shaggy clog of a mystery. Damon certainly has no nose for crime: at one point he's dead sure the kidnapper is an obese middle-aged twin who he believes is killing off the animals (a duck and two St. Bernards are also among the. . . Missing Six) to satisfy his craving for blood. Typically, the disgusting ""red liquid"" Damon catches Ollie drinking turns out to be borscht. That's just one of the bits of supposedly hilarious, off-base sleuthing that finally forces Damon to exclaim ""What a comedy of errors."" We only wish.