We begin in the dark, with a chase. There are dogs, there are explosions, and Morgana has caught someone.
It’s Alator the torturer. She wants to know one thing, the location of Emrys, but he refuses to blab.
This pleases Morgana, which is probably bad news for Alator.
The next day, Arthur, Merlin and Gwen are out for a picnic in the woods. Merlin and Gwen note that Arthur is uncommonly happy these days, but all is not well. Merlin spots magical scorch marks on the trees, and a half-buried medallion.
Back in Camelot there’s been an influx of refugees from the city of Helva, attacked by Morgana’s forces. This mystifies Arthur at first, given that Helva is tolerant of magical activity. Merlin goes back to the woods alone to investigate further, against Gaius’s best advice.
In the mist of dusk, Merlin finds evidence of a disrupted camp, bowls, torn paperwork. He takes the papers back to Gaius to see if he can translate. Gaius spots Alator’s signature, and realises what Morgana’s intent is, to torture the truth about Emerys out of the untortureable torturer.
And that’s exactly what she is doing. Physical torment doesn’t work, so she pulls out the Naithair, the black snake that can cause immense psychic turmoil. This brings a jolt of fear into the eyes of her prisoner.
Meanwhile, Arthur has sent Merlin to make Gwen a surprise breakfast in bed. As he gathers some wild flowers, he’s approached by a mysterious woman with a strange tattoo, hiding in plain sight. She knows his real name, tells him that Arthur’s enemies are close by, and demands to see him that night, alone.
Merlin draws the tattoo for Gaius, who recognises is as the mark of the Bendrui, an initiate in the ways of the old religion. While Merlin wants to act on the information she offers, wants to trust her, Gaius points out that she knows his name, and that’s likely to be because Alator has been broken. It’s a trap. Merlin agrees not to go.
At the ruined temple, the old woman, whose name is Finna, discusses something with a raven, using magical language and yet clearly saying the name of Morgana. This does not bode well.
Gaius has taken matters into his own hands, telling Arthur of Finna’s existence and warning him that she’s plotting against him. Arthur sends Mordred off to look for her, while Merlin mulls over his promise to keep away from Finna. After a lot of thought, he decides to go and see her, sneaking out past a sleeping Gaius.
Finna claims to be a servant of Alator’s, and speaks of Merlin’s role in protecting Arthur, but they are interrupted by Mordred’s men, who chase after them.
Using magical fire, Merlin helps Finna get away, and pledges to meet her again.
It seems the raven Finna sent was bound for Alator, could she be on the level after all?
Morgana is certainly frustrated that she cannot break him, but then her servants find the letter from Finna. Suddenly she has someone else to torture, so Alator is of no further use.
Gaius apologies to Merlin for putting Finna’s life in danger, there’s a hug, and Merlin goes off to try and put things right. She’s making her way out of Camelot, leaving a magical trail for Merlin to follow. Of course, he has to hide from Arthur’s men too, and that’s not his best thing. They find him, and insist that he stays in their care.
Just at the point at which the knights decide they’ve lost Finna’s trail, Morgana picks it up. Merlin attempts to sneak off to find Finna, but is interrupted by Mordred. Merlin tells him nothing, and Mordred lets him go with a suspicious stare.
Merlin finds Finna, then a lot of things happen at once. They are attacked by Morgana’s men, they repel them, but Merlin is hit by a crossbow bolt. Finna convinces him to stagger to a nearby watchtower, with Morgana in hot pursuit.
Inside the tower, Finna gives Merlin a small wooden box, to help with the dark days to come, and tells him not to trust Mordred “the druid boy.” Then she tells him he must go on alone, that she will see off Morgana herself, and if he goes up on the roof, the soldiers won’t find him. There’s an argument, she takes his sword, and he finally relents.
Finna faces Morgana alone, drawing Merlin’s sword and fending her off. She plunges the sword into her own stomach, and an appalled Morgana orders her men to burn the body as she leaves.
On top of the tower, Merlin calls to Kilgharrah to come and get him. He’s not in great shape. The great dragon arrives, bearing him away and healing his wound. The next day, Merlin awakes in the forest, and, noticing Kilgarrah’s fraying wing, offers to heal him. The dragon admits he’s old, that he won’t be around much longer, which rattles Merlin. He asks if he’ll ever see his dragon friend again, but there’s no answer, just the beating of wings on the wind.
Back home, Merlin and Gaius open the box from Finna, which contains a dark prediction: “Let loose the hounds of war. Let the dread fire of the last priestess reign down from angry skies. Brother will slaughter brother. Friend will murder friend. As the great horn sounds, a cold dawn at Camlann. The prophets do not lie. There Arthur will meet his end, upon that mighty plain.”
The realisation that so many people have suffered to deliver this message is a bitter pill for Merlin to swallow, but he has little time for introspection. A knight has been brought into Camelot, suffocated by the skin on his own face. It’s a punishment for the knights, and a stark warning. Morgana has declared war.