The central conflict arises when Queen Medb of Connacht launches a massive cattle raid against Ulster to seize the legendary Brown Bull of Cooley, triggering a devastating war. The narrative follows the young hero Cú Chulainn, who stands as the sole defender of Ulster against the invading armies while the rest of the province's warriors are incapacitated by a curse. The story is presented through a series of heroic episodes that blend prose and verse, detailing the tactical maneuvers of the war and the individual duels that define the conflict. The world is governed by ancient codes of honor, supernatural interventions, and the volatile whims of the Irish gods.

Readers and critics frequently highlight the accessibility of this translation, noting that it successfully captures the raw, archaic energy of the original Irish epic. Discussion often centers on the stark, brutal nature of the combat and the mythological depth of the characters involved. Many observers appreciate the inclusion of the preparatory tales, which provide necessary context for the central conflict. The artistic contributions of Louis le Brocquy are often cited as a significant enhancement to the reading experience, grounding the ethereal nature of the myths in visual form. The work remains a standard reference for those interested in the foundational texts of Irish cultural history.