Eve and the mermaid's tears - Jess Black

Eve and Oscar find themselves in a world where cut throat pirates rule the waves and where the language of the sea is the only tongue spoken. It's the mermaids who need help. They're being captured so that their tears can be sold as treasure. But if these protectors of the ocean disappear then the balance of the ocean is upset and all marine life is under threat. Can Eve and Oscar find their sea legs and help the mermaids?Keeper of the Crystals is an adventure fantasy series full of secrets and mystery. Eve and Oscar, two unlikely friends, accidentally tap into the power of crystals. They are thrust into different and dangerous worlds where unicorns, tigers, dragons and panthers communicate with people and where native communities and their way of life are under threat. What are the secrets of the crystal keeper and why does Eve have these powers?