Merlin ( series 3 ) - wikipedia Merlin ( series 3 ) Merlin ( series 3 ) Complete DVD set box art Country of origin United Kingdom No. of episodes 13 Release Original network BBC Original release 11 September ( 2010 - 09 - 11 ) -- 4 December 2010 ( 2010 - 12 - 04 ) Series chronology ← Previous Series 2 Next → Series 4 List of Merlin episodes The third series of Merlin began on 11 September 2010. Series three regular cast members include Colin Morgan, Bradley James, Katie McGrath, Angel Coulby, Anthony Head, and Richard Wilson, as well as Emilia Fox joining the regular cast. John Hurt took his previous role as the voice of the Great Dragon but was no longer one of the regular cast ( though he continued to provide the opening narration for the series ). Series three consists of 13 episodes. The series three premiere was watched by 6.49 million viewers. Series 3 introduced the format of a two - part opener and two - part finale, this format was retained for Series 4 and Series 5. The series was notable for the change in character of Morgana from the sympathetic heroine in the first two series to the villain in series 3, keeping with the historical concept of Morgana as Merlin 's nemesis in the legends of King Arthur. BBC officially renewed the show for series 4 on 10 October 2010. Contents 1 Plot 2 Cast 2.1 Starring 2.2 Recurring 2.3 Guest stars 3 Episodes 4 References Plot Merlin is the first to discover Morgana 's changed loyalties but he must tread carefully as Uther 's affection for his `` ward '' has increased with her one - year absence. Arthur is likewise blind to Morgana 's treachery, forcing Merlin and Gaius to be even more wary of detection as they thwart her schemes. Cast Starring Colin Morgan as Merlin Bradley James as Arthur Angel Coulby as Gwen Katie McGrath as Morgana Anthony Head as Uther Pendragon Richard Wilson as Gaius Recurring John Hurt as the Great Dragon ( voice ) Emilia Fox as Morgause Rupert Young as Sir Leon Eoin Macken as Gwaine Adetomiwa Edun as Elyan Michael Cronin as Geoffrey of Monmouth Tom Ellis as King Cenred Alice Patten as Ygraine Guest stars Mark Williams as the Goblin ( voice ) Karl Johnson as Taliesin Miriam Margolyes as Grunhilda Georgia King as Elena Simon Williams as Lord Godwyn Warwick Davis as Grettir Donald Sumpter as the Fisher King Pauline Collins as Alice Eddie Marsan as the Manticore ( voice ) Harry Melling as Gilli Ralph Ineson as Jarl Laura Donnelly as Freya Santiago Cabrera as Lancelot Tom Hopper as Percival Episodes No. overall No. in series Title Directed by Written by Original air date UK viewers ( millions ) 27 `` The Tears of Uther Pendragon - Part 1 '' Jeremy Webb Julian Jones 11 September 2010 ( 2010 - 09 - 11 ) 6.49 A year has passed with many fruitless quests in search of the missing Lady Morgana. The despondent Prince is all but ready to give up, but as he and Merlin recover from their latest skirmish a bruised, bloodied figure emerges from the mist ; it is the Lady Morgana. King Uther is overjoyed, but then starts to lose his mind. Merlin thinks that magic is the cause ; could this be the work of his dutiful ward ? The young warlock puts himself in grave danger trying to find out whose side Morgana is really on. 28 `` The Tears of Uther Pendragon - Part 2 '' Jeremy Webb Julian Jones 18 September 2010 ( 2010 - 09 - 18 ) 6.06 With Merlin gravely ill from the Serket 's poison, Morgana and Morgause continue with their evil plan. They have mentally incapacitated Uther and convinced his enemy, Cenred, to invade Camelot. The fate of the kingdom now rests on Arthur 's shoulders. The Prince and his Knights resist the invaders, but Cenred 's soldiers are not the only threat they face. Can Merlin stop Morgana in time to save Arthur from the enemy within ? 29 `` Goblin 's Gold '' Jeremy Webb Howard Overman 25 September 2010 ( 2010 - 09 - 25 ) 6.22 After stumbling into a secret chamber, Merlin releases a mysterious goblin with a penchant for making trouble and a lust for gold. It takes control of Gaius and causes all sorts of mischief. Merlin is desperate to find a way to free Gaius. 30 `` Gwaine '' David Moore Julian Jones 2 October 2010 ( 2010 - 10 - 02 ) 6.42 Merlin and Arthur find themselves outnumbered in a bar fight but an enigmatic young man helps them win. The man 's name is Gwaine and he risks his own life to protect Arthur but during his act of bravery he is seriously wounded. The Prince decides to take him back to Camelot where he could make a recovery with Gaius ' help. Meanwhile, two unscrupulous `` knights '' plot to murder the Prince. 31 `` The Crystal Cave '' Alice Troughton Julian Jones 9 October 2010 ( 2010 - 10 - 09 ) 6.36 When Merlin enters the Crystal Cave, an old sorcerer shows Merlin a vision of the near future in which Morgana appears to kill Uther. Events begin unfolding as they did in the vision and Merlin misinterprets Morgana 's nighttime visit to Morgause as sneaking off to kill Uther. Merlin tries to stop her, accidentally fracturing Morgana 's skull. Merlin can not live with Arthur and Uther 's extreme anguish over Morgana 's impending death and forces the Great Dragon to help save her. Unfortunately, a shocking revelation by Uther means that Morgana is more bitter than ever and Merlin now has to foil a real assassination attempt. 32 6 `` The Changeling '' David Moore Lucy Watkins 16 October 2010 ( 2010 - 10 - 16 ) 6.40 Uther has Arthur get engaged to Princess Elena, who arrives in Camelot. Elena is not dainty or lady - like and Arthur does not love her. Furthermore, her nanny, Grunhilda, is working for the Sidhe ( pronounced `` Shee '' ) Elder to use Arthur 's marriage to take over Camelot. As Merlin and Gaius battle Grunhilda to free Elena from the Sidhe, Arthur must decide if he will go through with the wedding. 33 7 `` The Castle of Fyrien '' David Moore Jake Michie 23 October 2010 ( 2010 - 10 - 23 ) 6.82 Gwen is kidnapped one night as part of a plot by Morgana, Morgause and Cenred. Cenred has Gwen 's estranged brother Elyan captive at Castle Fyrien and, after a quick reunion, releases Gwen with a choice : bring Arthur to Cenred or Elyan will die. Arthur, Merlin and Gwen plan to save Elyan by using a secret entrance to Castle Fyrien, but things get complicated when Morgana decides to come with them. 34 8 `` The Eye of the Phoenix '' Alice Troughton Julian Jones 30 October 2010 ( 2010 - 10 - 30 ) 6.92 Arthur sets out on a quest to retrieve the Golden Trident from the Fisher King 's Realm. But unbeknownst to Arthur, Morgana and Morgause have devised a clever plan to stop him from ever returning to Camelot. Once again, Merlin ( this time with the help of Gwaine ), must foil the plans of the ill - wishing sisters to save Arthur and discover the true purpose of the quest. 35 9 `` Love in the Time of Dragons '' Alice Troughton Jake Michie 6 November 2010 ( 2010 - 11 - 06 ) 6.90 When Alice, a physician and Gaius ' old love, returns to Camelot, he is smitten again. However, she brings a Manticore with a plan to kill Uther with poison from its scorpion tail. Merlin tries to tell Gaius, but he wo n't listen. 36 10 `` Queen of Hearts '' Ashley Way Howard Overman 13 November 2010 ( 2010 - 11 - 13 ) 7.37 Morgana has visions about Gwen being crowned as Queen of Camelot. Morgause tells her that to prevent this she must find a way to split Gwen and Arthur up. Morgana first leads Uther to Arthur and Gwen 's date, causing the king to banish Gwen from Camelot. When it seems that Morgana 's plan has backfired, Gwen is accused of being a sorceress thanks to evidence that Morgana planted in Arthur 's room. Merlin uses an ageing spell to disguise himself as the real culprit and save Gwen. 37 11 `` The Sorcerer 's Shadow '' Ashley Way Julian Jones 20 November 2010 ( 2010 - 11 - 20 ) 7.42 As another tournament descends on Camelot, a young man known as Gilli sets his sights on victory. Gilli uses magic in the tournament to win his fights, and by doing so he begins to realize the true strength of his powers and what glory he could possibly use them for. Meanwhile, Morgana manipulates Uther and Arthur into competing against each other. 38 12 `` The Coming of Arthur - Part 1 '' Jeremy Webb Jake Michie 27 November 2010 ( 2010 - 11 - 27 ) 7.12 Merlin and Arthur must save the Cup of Life before it ends up in the wrong hands. They manage to get it, but quickly lose it to Morgause. With an immortal army on side, Morgause takes over Camelot. Merlin and Arthur secretly watch in horror as Morgana reveals her true allegiance ( as well as her parentage ) and is crowned Queen of Camelot. 39 13 `` The Coming of Arthur - Part 2 '' Jeremy Webb Julian Jones 4 December 2010 ( 2010 - 12 - 04 ) 7.67 Morgana has taken Uther 's place on the throne, while Uther sits defenseless and alone in the castle dungeons. Gwen and Sir Leon escape from Camelot to join up with Arthur and his friends in exile. Despite the impossibility of facing an immortal army, they plan a counter attack to rescue Uther and Camelot. References Jump up ^ http://www.digitalspy.co.uk/cult/s53/merlin/news/a283945/merlin-renewed-for-fourth-series.html Jump up ^ `` Weekly Viewing Summary ( see relevant week ) ''. BARB. Archived from the original on 8 November 2008. Merlin ( TV series ) Episodes Series 1 `` The Dragon 's Call '' Series 2 Series 3 Series 4 Series 5 Related articles Characters Retrieved from `` https://en.wikipedia.org/w/index.php?title=Merlin_(series_3)&oldid=803617562 '' Categories : 2010 British television seasons Merlin ( TV series ) Hidden categories : Use dmy dates from November 2012 Talk Contents About Wikipedia Dansk Ελληνικά Français Italiano Edit links This page was last edited on 3 October 2017, at 16 : 22. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. 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Question: when does arthur find out about morgana being evil
Answer: "The Coming of Arthur - Part 1"