The Reversal Spell is a spell used to reverse recent magic. It was given to the Nowhere Gang by Miss O'Donnell, and requires a person to sacrifice something of value to themselves by destroying it while reciting the spell.
"Elements that speak as one, return their voice their work undone."
- Heath uses the spell as instructed by Miss O'Donnell, to reverse the truth spell the Nowhere Gang accidentally cast on themselves. He sacrifices his favourite book which he uses as a lucky charm.