The Merlin Effect combines scientific research procedures with the mythical stories of Merlin the magician and the conventions of modern fantasy. It tells the story of Kate Gordon and her father and their expedition to the coast of Baja California to search for a sunken Spanish galleon said to contain the lost horn of Merlin. Their research site also reveals unusual undersea volcanic activity, ancient fish that should be long extinct, local villagers with unusual longevity, and a group of ever-singing gray whales guarding a mysterious and dangerous whirlpool.
Always willing to test her limits, Kate gets sucked into the whirlpool where she meets Merlin himself, finds the horn, and battles with Merlin against the world's mortal enemy. Along the way, she resolves her relationship with her father, learns to make choices, and comes to understand her own powers of creation.