Martin and Elena are happily married, middle aged, comfortable. Perhaps a little too comfortable in fact, but this all changes when Martin goes for his customary walk in the forest and comes back with a special stone. Aside from the fact that it never seems to be quite the same shape, the stone seems to be listening, listening to what Martin and Elena secretly want in their deepest corners of their minds. And the stone is happy to change, and if sometimes its victims need some convincing, it is happy to provide a push...