When the tides in Damson Bay turn phosphorescent, a team of researchers from a nearby university establish a makeshift lab in an abandoned fishing storehouse to study the strange phenomenon. And while collecting samples of local marine life, Vivienne, a young research assistant, accidentally captures a creature seemingly risen from myth and previously unknown to science. The project's lead researchers quickly assume control of the discovery, and as their invasive scientific testing becomes more and more inhumane, Vivienne finds herself increasingly exploited and vulnerable to harm. With the creature wasting away in secrecy, Vivienne must find a way to release it from history and back into the sea.