Marina is new in Mermaids Rock, having travelled the world with her scientist dad, and she can't wait to make friends! She meets a group of mermaids who love animals and the environment as much as she does and the new friends soon face their first challenge... The beautiful coral caves nearby have been damaged. Who, or what, could have caused the destruction? And why?

Kai is really excited that Marina is coming to stay while her dad goes on a research trip to the Arctic - they're going to have so much fun! But when they don't hear from him for a few days they start to worry. Travelling through the whirlpool to see if they can find him, the friends are amazed by the icy scene and enchanted by the walruses they meet. But with no sign of Marina's dad and time running out, can the team work together to save the day?

Welcome to Mermaids Rock! The entrance to the mermaid realm in the deep, blue ocean… When animals start disappearing from the reef into the mysterious Midnight Realm, Naya and her friends investigate! There they find a glowing cave with a tentacled monster lurking within. Then it traps Luna and the friends launch into action. Naya will have to get inventive if she’s going to pull off her rescue mission... The fourth book in an exciting new series about the wonders of the ocean, perfect for fans of RAINBOW MAGIC, AMELIA FANG and Holly Webb.

When the magic whirlpool malfunctions, it sends Marina and her friends to a dark, underground river. Exploring the caves and adventuring along the tunnels, they discover a jungle with amazing wildlife. But then the whirlpool disappears - they're stuck! Stranded, the friends have to use all their skills to return home...

In this latest installment of the popular Mermaids Rock series, Kai and his friends take a trip to the Red Sea and explore a shipwreck—but when a group of divers shows up, will the friends be able to make it back to Mermaids Rock before being discovered? Kai, Marina, and their friends decide to use the whirlpool at Mermaids Rock to take a trip to the Red Sea. They find a shipwreck, and Kai is enthralled with the human artifacts that they find there. But Coralie is worried that they’ll be discovered and urges the group to return home. Then a group of divers arrives at the shipwreck, and the friends find themselves in a tricky situation. Will they be able to return to Mermaids Rock without being seen by the humans? Join Marina and her mermaid friends in the beautiful coral reef at Mermaids Rock ! Whether they're working together to help sea animals in danger or solving a mystery of the deep, the friends at Mermaids Rock will do anything to protect their ocean home and if there is a ripple of adventure, they will find it!