Eve and the mermaid's tears

Summary: Eve and Oscar find themselves in a world where cutthroat pirates rule the waves and where the language of the sea is the only tongue spoken. It's the mermaids who need their help. They're being captured so 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 before it's too late