In an agreeably Halloweeny spinoff of ``The Old Woman and Her Pig,'' Granny orders her cat to look under her bed to find out ``what's making that horrible, skin-prickling, hair-raising noise that keeps me from my book''; but neither the cat nor Granny's weary broomstick nor the troll under her stairs, the goblin in her bathtub, or any of the other creatures lurking around her house is biddable, despite her mounting litany. Finally she says ``BOO!'' to the bugaboo (who's busy baking teacakes), which frightens the bats, which scare the goblin...so that the cat chases the mouse out from under the bed and Granny can get back to her book. Nicely cadenced for reading aloud and equipped with comical cartoon-style illustrations with plenty of diverting haunted-house details, a lightweight story that's sure to please. (Picture book. 4-8)