It's Behind You (S01E05)

The team of paranormal investigators is summoned to assist a woman who witnessed a body drifting in the Potomac River, only for it to vanish. Insights from a local medium and the town historian link her sighting to a long-unsolved double murder from years past. As night falls, the investigators conduct a paranormal probe in the nearby woods and discover signs of possible satanic rituals or witchcraft taking place in Shepherdstown. They sense a sinister presence lurking in the darkness, a fear that intensifies when the medium warns that Bill's life is in danger.