When Molly Holmes moves with her family to Horseshoe Bay, her grandmother gives her an enchanted shell necklace that magically transforms her life. The power of the necklace transports Molly to the Undersea Kingdom, where she discovers that she is a Secret Mermaid and meets lots of new mermaid friends. But the evil Dark Queen Carlotta seeks to steal control from the good Merqueen Luna, by seizing the magic pieces of conch shell that help protect the...

Oliver Moon works hard at Magic School, practicing his spellcraft, toad-training, and broomstick-flying. But when he's entered for the Young Wizard of the Year award, he finds he's up against the top boy in his school, Merlin Spoonbender. Can Oliver cook up an extra-special potion to win the prize?

Oliver Moon thinks his luck is in when he wins the Magic School raffle, until he's presented with his prize - a hideous painting of an ugly monster. But could there be more to the picture than meets the eye?

Oliver's class is going on a school trip to a haunted house museum and Oliver is really excited about the ghosts he might see. But he didn't plan on the swarm of vampires that arrive in the middle of the night. Can he and his friend Jake work out a way to save his classmates from the bloodthirsty bats?

Molly must venture into the ocean's darkest depths to help find mermaid Pearl's missing shell. They know the Dark Queen's sea snakes are on the prowl - but nothing can prepare them for the discovery that Pearl's shell is inside a huge underwater volcano - a volcano that could erupt at any time!

Barney is having a wonderful time with Grandpa. Will the two of them ever get to sleep?

Molly must help her mermaid friend Delphi to find the second piece of the enchanted conch shell in time to prevent a terrible oil spill. Unfortunately, Delphi's shell is guarded by a spiky sea urchin, and the only way they can tempt it away is by bringing it some treasure from a spooky shipwreck, where a great white shark lurks, ready to attack. Can they save the day with the help of some humpback whales?

Many sea creatures have suddenly gone missing and Molly is determined to help her friends find them all. The seals have reported hearing strange, distant dolphin noises, so Molly and Aisha go to investigate. When they discover a magical shell with the thousands of tiny dolphins trapped inside, they have no idea how to release them.

Molly is called back by the Mermaid Queen because the mermaids desperately need her help. All the whales, turtles, seahorses, octopuses and dolphins have vanished from the seas and the mermaids expect dark magic is at work. Molly believes the answer to their whereabouts might lie in a strange sparkly ball she spotted in a rock pool.