Morgana and Helios lead their Southron army into Camelot, and it's only through Merlin's help and enchantments that Arthur is able to escape. Before he does, though, he sees Agravaine at Morgana's side and is stung by his uncle's betrayal. Still, Merlin is able to spirit Arthur away to neighboring Ealdor, while Morgana captures Gaius, Gwaine and Elyan and torments them for knowledge of Arthur's whereabouts.
En route to Ealdor, Arthur and Merlin are waylaid by the smugglers Tristan and Isolde. Tristan bears Arthur ill will for the taxes that led him to a smuggler's life, but reluctantly allows the king and his servant to join his party after Arthur saves Isolde from a soldier.
When the group arrives in Ealdor, Arthur is reunited with Gwen, and the two exchange an embrace and a reassertion of their love. The young king also apologies to Tristan for the tax issues, leading to an increased bond of friendship between the two men.
Unfortunately, Agravaine arrives soon after, having been dispatched by Morgana to track down the fugitives. Arthur, Merlin, Gwen, Tristan and Isolde escape, but with Agravaine in pursuit and Morgana in control of Camelot, the future looks bleak for our heroes and the salvation of the kingdom...
Mordred finds himself torn between loyalty and love.
Though Merlin is certain Mordred is at heart an enemy, the young knight is determined to prove his trustworthiness to the great Emrys.
In order to protect Merlin and bring harmony to Albion, Finna sacrifices her life rather than fall prisoner to Morgana.