Ten years after the death of his wife Siobhan, Brian CuCullen and his two sons, Kieran and Liam, are drawn back into the mysterious world of the Bene Lumen. Brian must resume his role as Tiarnan, a warrior for the light, while his two sons must go on to attend the mist isle-school Samhain. All the children who attend this school represent generations of Bene Lumen being trained as charmers, conjurers, casters, and warriors. Thousands of years ago, it was Merlin who created Samhain for the Bene Lumen. We find that Liam and Kieran hold a special place in the school, as one might be the next Merlin, and the other the next Arthur. Samhain School of Ancient Knowledge tells the tale of the Bene Lumen and the Illuminatii a war between the dark and the light; a war between extraordinary human beings and evil creatures, demons, and warped human beings; and the CuCullen Family play an important role.