In Invasion of the Mermaids (2025), a mysterious tsunami hits the California coast, uncovering a hidden underwater city. Marine biologist Dr. Leila Vaughn leads a government expedition, only to discover a race of ancient, intelligent mermaids led by the enigmatic Queen Thalassia.

Initially peaceful, the mermaids demand humanity stop polluting the oceans. When ignored, they launch coordinated attacks on naval fleets and coastal cities using bioluminescent siren songs to control minds. Leila discovers she’s part-mermaid—her mother was a defector from Thalassia’s court. As tensions rise, Leila must choose between humanity and her aquatic heritage. In a climactic confrontation, she sacrifices herself to broker peace, unleashing an ancient artifact that severs the mermaids’ control but saves both worlds. The film ends with a baby mermaid washing ashore near a child, hinting the story isn’t over. The invasion may be paused—but the tides are rising again.