Guy d'Alville had been a Knight of the Hospital before he was expelled from the prestigious military order for failing in his duties. He blames the loss of his fortune on one man: a Templar knight from Ireland named Robert Fitz William.
But in his quest for vengeance, Guy discovers ancient forces afoot in Ireland. The mysterious Otherworld is astir with rumours of war. The beautiful and terrible Aoife, Queen of the Night, is gathering her armies to assault the realm of mortals. Recognising a shadowed soul when She sees one, She promises Guy the High-Kingship of Ireland in exchange for his help. And, in time, the crown of England.
But Guy has unwittingly unleashed the frightening fury of the Nathairaí, whom some call the Watchers. Imprisoned for centuries within the Well of Dun Gur, once these malevolent creatures are free, their rampage will know no bounds.
Another traveller has come to the island: a young Benedictine monk with an uncanny gift for glimpsing the future. It will be his destiny to record the story of the Wanderers and the tale of the Watchers. But first he must solve a mystery, adjust to wild Irish ways and satisfy a burning hunger in his soul. For though he may not be aware of it, he has come to these shores seeking the mystical Well of Yearning . . .
