For as long as she can remember, twelve-year-old Emily Windsnap has lived on a boat. And, oddly enough, for just as long, her mother has anxiously kept Emily away from the water. But when Mom finally agrees to let her take swimming lessons, Emily makes a startling discovery -- about her own identity, the mysterious father she's never met, and the thrilling possibilities and perils shimmering deep below the water's surface. In a lovely twentieth-anniversary...

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.

Uncovering an ancient evil, Serafina, a mermaid of the Mediterranean Sea, searches for five other mermaid heroines who are scattered across the six seas, to save their hidden world.

As Serafina uncovers more clues about the talismans, Neela ventures into a sea dragon's nest, and Ling learns the identity of their foe.

Two children set out to capture a mermaid, but she manages to escape all of their traps.

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...

"The Princess in Black and her friends are enjoying a day of sun and sea on Princess Sneezewort's royal boat when a real, live mermaid princess emerges from the waves! Eeeeeee! Princess Posy needs their help protecting her very cute sea goats from being eaten by a very greedy kraken. But the princesses and the Goat Avenger quickly realize that fighting underwater can be tough for land dwellers, and only the mermaid Princess Posy can save the day....

As a mermaid versus human war looms on the horizon, Luce falls in love with her sworn enemy Dorian and assumes her rightful role as queen of the mermaids.

At the beach, Pinkalicious and her brother help a tiny mermaid, a merminnie, to go back home.

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?