Oona and her best friend Otto love to search for treasure...and often find trouble instead. Messy trouble. Tricky trouble. Even shark-related trouble. That's never stopped them before, though! After all, no proper treasure hunt is without some adventure. But when the grandest treasure yet is stuck in a deep, dark rift, Oona's not sure if she can dive right in. What might be waiting for her in those unknown waters?

Aqua, the mini-mermaid, takes Pinkalicious and Peter to her favorite seaside spots.

When Neptune tells Emily and her merman father and human mother to return to Brightport to try to make merpeople and humans work more closely together, Emily faces problems with old enemies, her new, half-merfolk friend Aaron, and a mystery related to a group of legendary lost sirens.

Experiencing occasional visions of the future, mermaid Kiki Coral receives a psychic warning that her classmate, Rocky Ridge, will have a dangerous encounter with a giant leatherback turtle, a premonition she fears nobody will believe.

"In this reinvention of Hans Christian Andersen's classic tale, a little mermaid trades her voice for legs and makes a new friend on land, but must return to the sea to save her family"-- Provided by publisher.

The New York Times best-selling series continues with the half-mermaid embarking on an icy and perilous journey to the Land of the Midnight Sun.Strange storms are blowing up from the ocean, caused by the nightmares of Neptune, King of the Sea. Convinced that his dreams herald an approaching threat, Neptune enlists half-mermaids Emily Windsnap and Aaron for a top-secret mission to find and eliminate the source of the trouble. But Emily and Aaron quickly...

"High-action adventure, a plucky protagonist, and whimsical illustrations enliven this sea fantasy, which will be most thoroughly appreciated by series followers." — Booklist
Picture an island set in a glittering blue sea, sparkling with white sand and palm trees, a secret place where humans and merfolk live together. To Emily Windsnap — half mermaid, half human — her new home is perfect. That is, until Emily ruins everything

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A shark has been spotted in Trident City! Pearl Swamp is so scared, she needs a shark Guard to escort her to and from school. She doesn't trust anyone who likes these terrifying creatures, especially Kiki Coral, who isn't nearly as frightened as Pearl. And to make matters worse, Pearl accuses Kiki of stealing her precious pearl necklace! Will the sharks destroy the peace of their sparking city? Or will the mergirls have to swim in dangerous deep-sea...

Barbie has an adventure as a mermaid. Preschool-Grade 1.

Shelly is a princess! A real princess! It's been a well-kept secret in Trident City, but now the word is out, and Shelly doesn't know how to act! Should she start wearing a glittery crown? Or move to a grand undersea palace? Will her friends have to call her Your Highness? Being a princess may be exciting, but Shelly's not sure she can truly play this royal part.