What is little mermaid fathoms below?

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The Little Mermaid: Fathoms Below is a middle-grade novel written by Suzanne Francis and published in 2019. It is based on the characters from the classic Disney movie "The Little Mermaid" and explores the backstory of the film's key characters.

The story follows thirteen-year-old Ariel, the youngest daughter of King Triton, who lives a peaceful life underwater until a storm at sea brings a human boat crashing into her world. Ariel becomes curious about the human world and their culture, and she starts exploring the surface world with her best friend, Flounder.

However, as Ariel learns more about the humans, she begins to question her own life and her family's strict rules about never interacting with them. Things become even more complicated when Ursula, the evil sea witch, offers Ariel a dangerous deal that could change her life forever.

Overall, The Little Mermaid: Fathoms Below is a charming and engaging story that will appeal to fans of the classic Disney movie and middle-grade readers who enjoy adventure and fantasy novels.