Beginning with the present-day ghostly disturbances driving teenager Rhiannon insane, the player journeys through a hippie commune, an Edwardian tragedy and pre-Christian myths. Magic and science are interwoven, with the 'Four Elements', the physics of combustion, astrology, Kirlian photography, Email, an ancient Celtic script and lots more all playing a part.

Rhiannon Sullivan is an emotionally vulnerable fifteen years of age. With her immediate family, she has moved to 'Ty Pryderi' ("Pryderi's House"), an almost derelict farmstead in a remote part of rural Wales, on the Celtic Western fringes of Great Britain.

Miles from friends and neighbours, and having ambitious and busy parents, Rhiannon must make her own life. A friend from the past visits briefly; there is a superficial Email exchange with a local girl, but by and large, Rhiannon is alone. Which is probably why parents Malcolm and Jen put their only child's increasingly wayward stories of unexplained noises and sightings down to a lack of stimulation and a consequently overactive imagination.

Rhiannon is adamant that these are not imaginings. Now the Internet lifeline in her room puts her in contact with historian and mythologist Jon Southworth. Through his special interest in the Mabinogion, Southworth knows that it is no coincidence that the house has the same name as a Welsh mythological character. He knows of the terrible connection to an age-old battle of man and magic. And he is learning ever more about the danger in the blurred, shifting lines between legend and fact; and between Then and Now.

As myth spills over into reality, Rhiannon has become engulfed, like her namesakes before her. There is a reason why this is happening now. Malcolm and Jen have done what little they can in taking their daughter away and leaving you to look after the part-home, part-construction site that is Ty Pryderi. But their absence can only postpone an ancient inevitability.