A menace dwells within the beach caves of Los Angeles, and he possesses Topaz's soul in an egg-shaped stone!
With Topaz's powers too weak to control him, the Werewolf runs from Buck Cowan's beach house. As he roams the shoreline, his attention is drawn to a light emanating from a cliffside cave, and he climbs up and creeps in. Within, he finds a strange figure, from whose body the red light pulsates. In front of the robed man, a ghostly form resembling Topaz lies upon a slab of rock, until the figure transforms it into a grotesque monster.
The Werewolf growls revealing his presence, and the man orders his creature to attack the man-beast. Their fight takes them to the cave's mouth, then over the cliff. The Werewolf, his fall is cushioned by the monster, runs off, and the mysterious figure tries to revitalize the dying creature with his mystic light.
The next morning, after Topaz and Buck find the again-human Jack Russell, and they hear his story, she explains that the man, Dr. Glitternight is after her. Once an ally of her dead father-figure, Taboo, Glitternight stole Topaz's soul while she was in India, encasing it within a large egg-like stone.
Glitternight finds the trio on the beach, renders them unconscious with his black light, then captures and binds them in his cave. The sorcerer reverts his dead monster into the ectoplasmic form of Topaz and returns it to the egg. The moon then rises, causing Jack's transformation. The Werewolf breaks his bonds and attacks Glitternight, but a mystic blast throws him against the egg, which shatters. Topaz's released soul now coalesces into an even more horrid creature. The Werewolf battles the monster, but cannot gain the upper hand. Using her telepathic powers, Topaz's amplifies the lycanthrope's savagery. In the struggle, the demonic thing is forced to impale itself upon a jagged stalagmite, then it dissipates.
Glitternight takes his leave, his parting words confusing Topaz: he shall return and Taboo shall die.