In the prequel movie to the Slayers television series, Lina Inverse and her travelling companion and rival, Naga the Serpent, set out for Mipross Island in search of its famous hot springs. However, their plans are derailed when they become embroiled in a plot orchestrated by a powerful mazoku named Joyrock. Joyrock has decimated the island's elven population and absorbed their abilities. In their quest to stop Joyrock, Lina and Naga encounter Rowdy Gabriev, an elderly mage who is determined to avenge the death of his beloved elf and defeat Joyrock once and for all.