Kitty helps her best friend Unicorn accomplish his dream of being a mermaid, but despite an elaborate DIY mermaid tail, the friends' trip to the beach does not go as planned and Unicorn's insecurities emerge.

Sweet, awkward sixteen-year-old Ruby Gillman is desperate to fit in at Oceanside High, but she mostly just feels invisible. She's math-tutoring her skater-boy crush, who only seems to admire her for her fractals, and she's prevented from hanging out with the cool kids at the beach because her over-protective supermom has forbidden Ruby from ever getting in the water. But when she breaks her mom's #1 rule, Ruby will discover that she is a direct descendant...

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

Once again Abby and her brother Jonah go through the magic mirror in their basement, and this time they find themselves interfering in the Little Mermaid story--and needing to set things right and make sure everyone has a happy ending.

"All Emily Windsnap wants to do is impress her best friend, Shona, and the other mermaids who live in the sea around Allpoints Island. But instead, she wakes up with the kraken, a terrifying octopus-like monster the size of an apartment building. Now he's coming after everything and everyone, and it's up to Emily to stop him. Luckily she's got help from Shona and one other person--someone Emily hoped never, ever to see again."--Back cover.

Transformed by the goddess Yemoja into a Mami Wati, an African mermaid charged with collecting the souls of those who die at sea, Simi goes against the gods to save a living boy, Kola, from drowning.

When she incurs Neptune's wrath by finding a diamond ring buried under rocks in the ocean, Emily is put under a curse that will force her to choose to be either a mermaid or a human and split up her parents forever.

When young Pearl, a mermaid, becomes caretaker of a single grain of sand, she discovers that performing even the smallest task well can transform the world.

Oona the mermaid is friends with everyone, but when her attempts to befriend a shark with sensory issues fail miserably she realizes what may be fun for her may be overwhelming for him.

When Pinkalicious and Peter go to the hidden cove to meet their friend Aqua, a mini-mermaid, they see pirates instead.