When the arrival of a mysterious girl proves this folklore all too true, the battle between man and sea takes a very vicious turn as these predatory beings return to reclaim their right to the ocean. The series stars Alex Roe as Ben, a bright marine biologist who finds himself drawn to Ryn, a mysterious new girl in town played by Eline Powell, who is a strange young woman with a deep dark secret. Fola Evans-Akingbola stars as Maddie, also a marine biologist who works with Ben, and is highly suspicious of Ryn. Ian Verdun stars as Xander, a deep sea fisherman on a quest to uncover the truth; and Rena Owen as Helen, the town eccentric who seems to know more about the mermaids than she lets on. Based on a story by Eric Wald and Dean White who both serve as executive producers.