En route back to the united states, the plane carrying Abigail, Matt and a stowaway Swamp Thing, crash lands in the Scottish moors. An older couple with a horse-drawn cart rescues Abigail, Matt and the pilot and takes them to their isolated mansion. But there's something not quite right about this family, and when the pilot returns to the wreckage of the plane, he's attacked by a creature that may even be a match for the Swamp Thing!