Breanna Ban Morna manages to free her Chief but fails to slay her Norse father as they escape from Dun Garm. In a fierce battle with his Dreadriders, Ćroí Dàn claims Erin's Hero as she single-handedly defeats the Norsemen.

Able to seek refuge at Dun Uisneach, the Aos Dána at the large hillfort first notices that Breanna carries Lann Dàn across her back, and then the Heart of Destiny reveals herself. Now, with the full backing of the Druids and the Chief and Chieftess of the dun, Erin's Hero leads her growing band of warriors to seek out Lia Dàn while evading the Dreadlord's pursuit.

Yet, while they follow a path southeast to some ancient standing stones that will allow them passage to Falias, also known as Tír na nÓg, the magical realm of the Tuatha Dé Danann, they find themselves in a stand-off at a river crossing with the Dreadlord and his Norsemen once more. Before any battle can take shape, ancient enemy demons emerge from the river.

Breanna must use her magical ring to summon the Tuatha Gods to save them. Manannán Mac Lir answers the call this time, battling the foul Fomorians, ensuring her band can enter Falias without further interference.

With help from Dadga and having acquired the Stone of Destiny from Danu, Erin's Hero returns to her realm, where she must seek Erin's Altar to wield the magic of the Triple Dàns, an act that will remove her father and his ilk from her land. Breanna's Band must battle the Dreadlord and his Norsemen to give Erin's Hero the time to make such a feat possible-a feat that will warp the Emerald Isle's fabric of time and could claim Breanna's soul!.