Jodie hates her life and her looks, but when she wakes up one morning as a stegosaurus things are even worse. Coping with school is impossible and when her parents take her to the doctor, Jodie is kidnapped by an unscrupulous consultant, Mr Pinkerton-Snark, who plans to exploit her to make his fortune. Jodie's younger brother rescues her from hospital and the two make a mad dash through town trying to escape. Jodie is recaptured but her brother has a brainwave about getting her back to normal and turning the tables on Mr Pinkerton-Snark. A girl again, Jodie realise that families are great, however much they may fight.