The sparkling blue waters of Never Land hide creatures as fascinating as they are unpredictable, and the fairies have always strictly avoided the local mermaids. Everyone in Pixie Hollow agrees that mermaids are nothing but trouble, known for their vanity and mischievous tricks. However, the youngest of the Never Girls, Gabby, has never been one to listen to rumors when it comes to making new friends. During a visit to the lagoon, Gabby strikes up an unlikely friendship with one of the mysterious mermaids beneath the waves. Kate, Mia, and Lainey are immediately alarmed and desperately try to warn their little sister to stay away before she gets hurt. But Gabby sees a different side to her aquatic new friend and absolutely refuses to turn her back on the relationship. You get to dive into a beautiful underwater adventure that tests the boundaries of loyalty and trust. The girls must figure out if the fairy legends are true, or if Gabby's open heart has discovered a secret the rest of Never Land has completely misunderstood.