 Graeme makes an antidote to counteract the disastrous effect of his growth mixture and reduce Twinkle back to the normal size of a cat, but the Goodies have to disguise themselves as giant mice, and become airborne on their trandem, to be able to get close enough to Twinkle for the antidote to be successful — following which their "hot-air trandem balloon" is carried away by a Concorde airliner.Twinkle returns to normal size, and all seems well.However, the Goodies discover that there is yet another unexpected and unforeseen consequence resulting from Graeme's growth mixture — they now have a king-size mouse problem on their hands.