On the anniversary of his coronations and his father’s death, Arthur and Camelot learn the lesson of just how dangerous ghosts of the past can be.
After a bit of hunting in which Merlin’s incessant sneezing has ruined, Arthur and his manservant hear frightening screams. They come across a village ready to burn an old woman at the stake. Arthur intervenes and despite finding out she’s been accused of sorcery—without a trial, no less—Arthur distinguishes himself from Uther Pendragon, who would have himself taken the torch to set the woman ablaze, by removing her from the villagers’ and her fiery fate. They take her away but Merlin realizes she won’t make it through the night. The old woman accepts her fate and, for his kindness, she blesses (or curses) Arthur with a small, ornate horn. Her final words to him are that it has the power to summon the spirits of the dead and to use it wisely.
When they return to Camelot, they show the horn to Gaius who identifies it as the Horn of Kathbad, a powerful tool thought lost during one of Uther’s raids. Gaius vouches for its efficacy, taking part in past summation rituals with it, using the Great Stones of Nemeton as a focal point to access the spirit world. Later that night, a morose Arthur (for his coronation celebration marks the death of his father as well) visits his father’s tomb before coming to a decision.
The following day Merlin enters his master’s chambers and realizes Arthur is hiding something. Despite the warnings, Arthur and Merlin travel to Stonehenge, err the Stones of Nemeton, to summon his father. Though Merlin tries reminding him the dangers of such powerful magic, Arthur asks his friend were the role reversed would he do the same. The answer is obvious and Merlin defers as Arthur blows the horn and is beset by wind and light. He walks through the light and Uther Pendragon awaits him. But this is no tender reunion. There was nothing soft or compassionate about Uther in life and it is the same in death. He is quite critical of his son, lambasting him for ignoring tradition and ancient law. His criticisms ignore the gradual improvement on life Camelot has enjoyed since Arthur’s reign and due to his respect for his father, Arthur has trouble remembering his own accomplishments. Uther has always ruled through fear and power, the only ways he knew and doesn’t believe that the people respect Arthur for his son rules through compassion. The conversation highlights Arthur’s biggest weakness; his desire to make his father proud and lack of conviction when his own actions go against Uther’s designs. Uther dismisses his son though tells Arthur that he loves him; before he leaves the spirit world, Arthur glances back at his father.
Arthur is tormented by his father’s words and Merlin reminds him that the people do respect him. At the roundtable, they are going over the daily report when the doors are thrown open by a wind conjured from nothing and the candelabra falls onto the table. Merlin can’t help but wonder on the cause and his suspicions grow when he feels an ominous wind whisper through the corridor. Not long after Merlin’s experience, Percival investigates strange sounds in the knight’s hall when an axe hurled by an invisible force embeds itself into his shoulder. Gaius patches him up and Percival admits he sensed a presence just before the axe fell. After the knight leaves, Merlin tells Gaius about Arthur using the horn and the elder man is upset Merlin didn’t heed his warnings. He also says that during the ritual the summoner was never to look back, for it would offer the spirit entrance into the world of the living. Merlin takes the information to Arthur, who admits he may have “glanced around”. Still, he’s hesitant to believe Merlin’s theory that Uther would do such a thing, dismissing Merlin when the thought becomes too much.
Uther doesn’t stop at a knight who doesn’t come from nobility or attacking the roundtable. As Gwen traverses down the halls by herself, she’s attacked by the invisible force. She holes herself up in a storage room only to be KO’d by a flying jar. She lay defenseless as the room catches fire but Merlin happens to come along and saves the queen from an untimely death. The attack on Gwen is all the proof Merlin needs to identify this as the works of Uther and they go to Gaius for help. He tells them that Arthur—for he was the one to summon the spirit—will have to send Uther’s spirit back using the Horn. Gaius concocts a potion that will allow them to see Uther in his spirit form and then use the Horn. The tension of the situation is temporarily abated when Arthur forces Merlin to drink first. “At least we know it doesn’t kill you instantly,” the King remarks before downing the contents of the vial. His disgusted face and remark on it being the “foulest thing [he’s] ever tasted” is only bested by Merlin’s satisfied “Did I forget to tell you about that part?”
Ready for the mission ahead, the two make their way through the castle and stumble into Sir Leon. To throw the knight off their true purpose, Merlin says he’s teaching Arthur about poetry. It’s one of few opportunities Merlin has in getting a sharp dig in to his King and best friend and he does quite the job. Levity aside, as they traverse the halls, Merlin again reminds Arthur just how beloved he is as King, how people believe in and love him. But as we all know if we do not believe in ourselves, it doesn’t matter what others feel and Merlin is sure to remind Arthur of that fact.
The two split up with Merlin searching the storage areas and Arthur other parts of the castle. The latter arrives at the throne room
where the ghost of Uther sits as if it remains his to occupy. Arthur wants to know why Uther is doing this and his father’s shade is unforgiving, citing Gwen as a weakness and Arthur unable to follow Uther’s path. Merlin’s speech may have been the nudge Arthur needed for he tells his father “I have to do what I believe right.” He finally accepts that he will never be his father and tells Uther as such. “Camelot comes first,” Uther replies before knocking Arthur unconscious. He’s ready to kill his son but Merlin intercepts him, revealing his magic in the process. He tears down the former king, releasing all the pent up frustrations the years of hiding who he was to Uther. When Uther tries to attack, Merlin plasters him back into the ether with a well-timed hadoken. Merlin searches the corridors for Uther who is, in turn, quietly stalking the young wizard. He eventually gets the drop on Merlin but before he can strike Arthur intervenes, showing the Horn to his father. Uther tries pleading with him, saying he has only do for Camelot but Arthur is not deterred. Uther has had his time, it’s now Arthur’s turn to rule as he sees fit. Uther attempts to tell his son about Merlin’s magic but is sent back to the spirit world before he’s able to form the words.
Once again our two heroes have saved the day and as they reflect on the world Arthur is in the midst of creating, he dismisses his attacks on Merlin as horseplay. Merlin uses the words as permission to slap Arthur quite violently in the back of the head with his own glove. His nervous reply of it being horseplay is met by Arthur calmly donning the glove and making quite the intimidating fist before showing Merlin the true aspects of horseplay.
Even though Arthur has been king for several years, it hasn’t been until this episode where he’s ready to come into his own. He’s lived in his father’s shadow for too long, second guessing his own actions and it has taken Merlin to help keep him on that path. It’s a path that, after his final meeting with his father, Arthur will remain true to himself, no longer wondering if he’s making his father proud. For as Uther said, Camelot is more important, an ideal that Arthur has followed since the beginning.