Successful archaeologist Fiona stands on the threshold of a great discovery. She has found a way to prove whether the pagan goddess Morrigan is a historical figure or a mythical demon. Together with her daughter Lili, she sets out to the so-called Island of the Mummies. After the opening of Morrigan's sarcophagus on the island, creepy things begin to happen to Lili. Fiona and her team will have to uncover an ancient secret to stop the primal evil and save her daughter.