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So, you are no longer the last of your kind.
Merlin to Kilgharrah

Aithusa was the fourth episode in the fourth series of Merlin which was first broadcast on the 22nd of October 2011.

Synopsis Edit

The mysterious Julius Borden arrives in Camelot with the news of a magical secret that threatens to change the landscape of the kingdom for ever, as the fantasy drama continues. He has located the final part of the key to the Tomb of Ashkanar – an ancient mausoleum which holds a very special treasure: the last remaining dragon's egg.

Plot Edit

A man named Julius Borden goes to a Druid camp at night, stealing two parts for a model and attaches them. When he is caught by the Druids, he escapes with the parts after threatening to kill one of the Druids. Borden later arrives in Camelot and goes to Gaius’ chambers. He asks Gaius to help him find the last part of the model which is in fact the Triskelion, the key to the tomb of Ashkanar which holds the last remaining Dragon's Egg.

Triskelion single s04e04

Julius Borden stealing a piece of the Triskelion

As the last part is in the vaults of Camelot, a suspicious Gaius refuses to help him and tells Borden to leave. Gaius tells Merlin, who overheard their conversation, that Borden was once his pupil before the Great Purge separated them. When Merlin mentions the Dragon's egg, telling Gaius that it is the only way he can preserve the Dragons, Gaius warns Merlin that Borden is not a man to be trusted. Merlin later summons Kilgharrah, who tells him that he feared until now that the egg would never be found and that he worried that he would be the last remaining Dragon. Kilgharrah then tells Merlin to retrieve the egg and Merlin promises to do so.

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Borden piecing together the Triskelion.

The next day, Merlin visits Borden and promises to help him find the last part for the triskelion with Borden reluctantly agreeing. Merlin later steals a key to the vaults from Arthur and gives it to Borden during the night who knocks the guards out and finds the last part. After attaching the last part to the triskelion, Borden knocks Merlin unconscious and escapes. Merlin awakens in the morning to learn that the theft has been reported to Arthur, who knows of the tomb containing the last Dragon egg. Arthur plans to pursue Borden and destroy the egg so that magic is driven out of Camelot. Before Merlin leaves, Gaius angrily tells Merlin that his actions have cost the egg's safety within the tomb as Arthur plans to destroy it and that he is unsure what Borden will do with the egg.

Percival attacked

Under attack

Merlin then leaves Camelot with Arthur, Leon, Percival, Elyan, and Gwaine to pursue Borden. As they camp during the night, Merlin hears a voice inside his head calling to him and it leads him to the Druids. The Druids tell Merlin that Borden has stolen the triskelion parts from them and that the way to the tomb is at a place which appears to be a dead end. They also warn him that the key is also a trap, as is the tomb itself. As Merlin continues with Arthur and the others, they go through a cave which is the dead end the Druids mentioned and find the entrance to the tomb. However, Borden attacks them with a crossbow, wounding Percival, but Merlin disarms him with his magic, forcing him to flee.

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The Triskelion completed.

Merlin - I am the Last Dragonlord

Merlin - I am the Last Dragonlord

Julius Borden faces Merlin

Later, Borden secretly spikes their food with a poison which Arthur and the others eat. Merlin soon discovers that all of them are unconscious due to the poison, forcing him to cure them and pursue Borden to the tomb alone while they are sleeping. As he reaches the tomb, he finds Borden opening the tomb with the triskelion, only to get knocked out by a gas. Merlin continues the journey and discovers the egg. Borden, however awakens and tells Merlin to give him the egg, promising that they will together have power and live like kings but Merlin refuses, realizing that Borden only wants the egg for power.

Borden attacks Merlin with his torch but is blasted across the tomb by Merlin's magic, knocking him out or killing him. Merlin retrieves the egg but causes the chamber to collapse, forcing him to escape with the egg while Borden perishes as the tomb completely collapses. After escaping, Merlin finds that Arthur and the others are awake and when Arthur asks what happened, Merlin tells them that the tomb was also a trap and Borden set it off causing the tomb to collapse and kill him. Merlin also tells them that the egg was destroyed when the tomb collapsed so that it's protected from Arthur.


The newborn Aithusa

Merlin S4 04

Merlin S4 04.04 Aithusa - The summoning of Aithusa

The summoning of Aithusa

After returning to Camelot with Arthur and the others, Merlin tells Gaius that no treasure can compare to the egg and Gaius tells him that the egg's fate now rests within Merlin. Merlin takes the egg to Kilgharrah who tells him that a Dragons egg can only be opened by the Dragonlords if they give the Dragon a name. As Merlin is the last Dragonlord, he opens the egg by naming the new Dragon Aithusa. After Aithusa, who is a white Dragon, hatches, Kilgharrah tells Merlin that the white Dragon bears the sign of the new world which Merlin and Arthur will build together.

Cast Edit

Main CastEdit

Recurring CastEdit

Guest CastEdit



View the transcript here.

Release & ReceptionEdit

  • 22 October 2011 at 8.15pm on BBC One and BBC One HD
  • In America- 27 January 2012 at 10:00pm on Sci-Fy

Behind the ScenesEdit

  • Aithusa's name - given to it by Merlin when he summoned it from its egg - means "Light of the Sun" in Dragon Tongue.

Production ErrorsEdit

  • Neither Merlin nor any of the Knights carry a pack big enough to contain the cauldron, plates, and spoons that they are seen using when they camp.


See alsoEdit

Series 4
The Darkest HourThe Wicked DayAithusaHis Father's SonA Servant of Two MastersThe Secret SharerLamiaLancelot du LacA Herald of the New AgeThe Hunter's HeartThe Sword in the Stone
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