By Jonathon Dornbush
Updated July 10, 2015 at 09:07 PM EDT
Credit: Jason Merritt/Getty Images

Having already found its King Arthur, Once Upon a Time is fleshing out its take on Arthurian legend with the casting of three new roles.

EW can confirm that Elliot Knight (How to Get Away with Murder and By Any Means) has been cast as Merlin, Joana Metrass (Sinias de Vida) will play Guinevere, and Andrew Jenkins (Wayward Pines) will guest star as Percival. Deadline originally reported the casting.

EW previously revealed that Liam Garrigan is set to to play King Arthur in season 5, during which executive producers Adam Horrowitz and Edward Kitsis promised they’ll put their “own twist on Camelot, on Arthur’s background and on his relationships with Merlin, Guinevere and Lancelot.”

For more on Once Upon a Time, check out our exclusive look at Emma’s transformation into the Dark One and read the show’s producers answer your burning questions. Once Upon a TIme returns for its fifth season on Sept. 27.

Episode Recaps

Once Upon a Time

Everything you’ve ever read about fairy tales is true—the residents of Storybrooke are living proof.

  • TV Show
  • 7
  • In Season
  • ABC
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