The3Tails: A Mermaid Adventure (2015)

Plot

Emily, Selena, and Jackie, beloved by their 50,000 YouTube followers as The 3 Tails, transition from online stars to cinematic heroines. With a special gift that allows them to transform into mermaids, the girls have kept their secret hidden, even from their families. However, their peaceful existence is shattered when a stranger discovers their abilities and kidnaps one of them to exploit her DNA. As they embark on a daring rescue mission beneath the waves, they uncover shocking truths about the threats facing not just mermaids, but all marine life.