Medusa is first shown destroying a dam when she notices a grasshopper crawling towards her. Medusa laughed evilly before turning the insect to stone with her gaze. After morphing into her human form, Medusa saved Holly from the effects of the dam's destruction, and later takes her to her garden. However, the evil Medusa actually planned to add Holly to her collection of statues and stone figurines, just as she would later do to Spike, a triceratops who attacked the garden. She also sent her living plants after Jack, Will, and Cha-Ka in an attempt to keep them from rescuing Holly. However, they managed to free Holly, drawing the ire of Medusa, who chases after them. Medusa is defeated when Jack forces her to look into her mirror, turning Medusa to stone.