Mermaid kittens and best friends Angel, Shelly, and Coral dive headfirst into working on their art project together, until their fun is nearly ruined when they run into their rivals, a trio of purrmaids called the Catfish Club.

"When it seems like her friends don't want to celebrate her birthday, Angel leaves the party and finds Minnie, a manatee who needs help!"--

After a field trip to learn about new foods, purrmaid friends Shelly, Angel, and Coral decide to cook a surprise meal for teacher Ms. Harbor and her friend, but unexpected challenges arise.

"All of Kittentail Cove is excited for Fish-mas, but things begin to go wrong when Coral is unable to mail her little brother's letter to Santa Paws in time"--

Purrmaid Shelly is taking care of sea horse and new class pet, Bubbles, who looks mysteriously unwell; luckily Shelly and her two best friends discover how to perk Bubbles up, and in the process learn why some animals are not meant to be pets.

Half unicorn, half mermaid Sirena is excited to start Mermicorn Magic Academy, but she soon realizes that magic is much harder than she imagined.

Mermicorns Serena and Lily try to use simple invisibility magic while doing a school project about magical mistakes, and learn a powerful lesson about using magic responsibly.

Shelly is hosting new student Leeza, a grrmaid, at her house, but becomes jealous when Leeza seems more interested in being friends with Coral and Angel.