On the eve of Solstice, Cait, a young woman belonging to Britannia’s Cantii tribe, awaits a rite of passage that separates girls from women. However, 400 ships, carrying 20,000 Roman soldiers, land on the shores close by, under the command of General Aulus Plautius, to take Britannia in the name of Emperor Claudius

Pellenor is convinced they can destroy the Romans using force but when Kerra learns of the suffering of their Celt prisoners, she seeks an alternative approach. Cait struggles to connect with Divis and his unusual ways, and soon finds she is left to fend for herself in the forest. An attempted mutiny goes wrong. Aulus finds an ally in the Cantii’s longstanding enemy, Queen Antedia of The Regni and seeks answers from an unexpected source –Veran of the Druids.

Aulus returns from his visit to the Underworld. The captured Romans face torture at the hands of King Pellenor. Pellenor is furious to learn of Kerra’s secret trip to the Romans. Divis persuades two Romans to get him into the Roman Camp. Sawyer’s brave stand against his oppressors leads to a violent end. Armed with the knowledge of her father’s survival, Cait reunites with Divis and forces him to adjust his plans.

Veran leads his troupe of Druids to Crugdunon Fortress to deliver judgment to Kerra. Events take an unexpected turn and lead to a grand emotional sacrifice and a new order for the Regni. Cait reveals the truth of sister Islene’s demise to her father. Aulus serves his own unique sense of punishment to the Roman mutineers.

The Druids prepare Pellenor for burial. Kerra is given till dawn to decide if she wants to be Queen. Lindon offers Kerra an alternative path. Phelan struggles to come to terms with the recent events while Amena spirals down a self-destructive path when all her ambitions come crashing down. Aulus visits Queen Antedia of the Regni. Divis seeks answers in the Underworld.

Divis is possessed by Pwykka and has a deadly mission. Kerra adjusts to her new role of Queen of the Cantii. Amena channels deadly intentions towards Kerra. Cait and her father find peace at Crugdunon but it is short lived once her significance is revealed. Roman mutineer Brutus fears his secret will be revealed with soldier Vitus’ return. Aulus agrees to talks with Kerra but is sidetracked by his own personal mission.