A survey vessel trawls up a man's body in the Outer Hebrides and ship's engineer Helen finds a compelling green stone in his pocket. On Rannoch Moor, her cousin Malcolm, a local ranger, is visited by a strange woman. She goes missing, and he too finds a green stone. The cousins have stumbled upon a multi-faceted conspiracy involving the high-tech company Fundamantal Forces who are promising limitless green energy from under the moor. It's soon...