Elliot Knight Elliot Knight

Been wondering who will be joining Once Upon a Time as Merlin and Guinevere? Well, you're in luck. Elliot Knight has been cast to play the famed wizard, while Portuguese actress Joana Metrass has landed the part of Guinevere, TVGuide.com has confirmed.

Knight has already gained some experience in the fantasy genre, having played Sinbad in the British Sinbad series. As we already know, Merlin will be a leading player in the upcoming fifth season - he is the one who knows how to save Emma from her new (and self-inflicted) fate as the new Dark One.

Metrass will play the "headstrong queen" Guinevere, who must balance her own happiness with the well-being of Camelot, as she fell in love with her husband King Arthur's most trusted knight Lancelot.

Meet Once Upon a Time's King Arthur

Wayward Pines actor Andrew Jenkins will also be guest-starring as Percival, another of Arthur's knights.

What do you think we can expect when Once Upon a Time returns? Hit the comments!

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