On a remote Scottish island stands a lighthouse. Mysterious and terrible events have happened on this island, starting with a witch hunt. Now, centuries later, Liv Stay flees to the island with her three daughters in search of a home. She doesn't believe in witches, or dark omens, or hauntings, but within months, her daughter Luna is the only one left. Twenty years later, Luna is drawn back to the place her family vanished, and it's up to her to find out the truth. But what really happened at the lighthouse all those years ago?