In search of new clues, 14-year-old Amy Cahill and her younger brother Dan travel to Australia, where they meet their closest relative, Uncle Shep. Together with him, they descend into the underground city of Coober Pedy, where the traces of their parents lead. Amy suddenly begins to remember the details of the night when the fire occurred, leaving her and her brother orphans. These memories frighten her so much that Amy does not dare to tell even Dan about them. Captured by the ghosts of the past, involved in a deadly struggle, Amy and Dan stop trusting each other and can no longer understand who is their friend and who is their enemy. This leads them to a fatal mistake... and the death of a secret ally.