for The Skull of Truth by Bruce Coville and Gary A. Lippincott
Mr. Elives's magic shop is back, and this time it is on the other side of Tucker's Swamp. And Tucker's Swamp is where Charlie Eggleston heads to escape a beating-for lying. Charlie can't seem to keep from lying, though sometimes his lies are for a good cause. When Charlie stumbles into Mr. Elives's magic shop, his eyes light upon The Skull. Charlie steals The Skull and it puts him under some sort of spell-he can only tell the truth. Trouble is, now no one believes him. . . .
Publisher description retrieved from Google Books.