Ghost Circles is the seventh bone book in the series. The term, Ghost Circles, has a big meaning in the actual story. In the series, a Ghost Circle is generally just a cold spot that sends a chill up your spine. They, in the series, are unleashed on the valley and cause mass destruction. They send all the trees in the valley to the dimensions inside them and The Lord of the Locust destroys the mountain, and sends volcanic eruptions and an ash plume over the valley. If, at that time, anyone or anything got in one of them, they would be between the small line between life and death. This makes them lethal to anyone who cannot see and find any way between them. The only ones who can see them are Briar, Thorn, Ted, and The Lord of the Locusts himself.