Terrified of the world, Sylvia lives with her mother in a luxury penthouse apartment. For Sylvia, everything is a cause for fear and panic. Isolated and friendless, she has no interest in the outside world at all. And then, one day, her mother unveils her latest purchase. A mermaid. A real, live mermaid, captured and placed in a water tank. For Sylvia, the mermaid is both terrifying and fascinating. Repulsive and beautiful. Soon, however, Sylvia discovers that the mermaid hasn't just been brought to London so it can be put on display. And as the mermaid makes plans to escape its terrible fate, Sylvia is thrown into a horrific battle for survival. The Mermaid's Revenge is the story of a scared little girl who comes face to face with the true horrors of the natural world.