The summer solstice is celebrated around the world, but in one place it holds particular meaning: the mysterious monument of Stonehenge.
The day you get back to London from an archeology dig, your friend Twig has an urgent request. Can you meet a man named Alastair at the Stonehenge monument? Alastair claims to have knowledge of the fabled missing "heelstone" so you agree to go. When you find Alastair, he is in deep trouble and passes along something more dangerous than some archaeological gossip.