Angel Coulby gets some juicy scenes in Friday's episode of "Merlin," but she had to watch her toes whiles shooting them.

"I really enjoyed my scenes with Tom Ellis; he's such a lovely guy, but he's really good at playing an evil king," Coulby said. "There was a scene where he was menacingly circling and tormenting me, baring down with that evil stare, and then he accidentally sort of stepped on me and said so sincerely and out-of-character, 'Oh, I'm really sorry,' and we all laughed."

In "The Castle of Fyrien" (9 p.m. Feb. 25, Syfy), Morgana (Katie McGrath) leads Arthur (Bradly James), Merlin (Colin Morgan) and Gwen into a trap set by nefarious King Cenred (Ellis), an ally of Morgause (Emilia Fox). Cenred forces Gwen into choosing one person to save, her estranged brother, the warrior Elyan (Adetomiwa Edun), and Arthur.

"It was a fun episode because I'm really desperate to do any action sequences. Gwen is generally indoors in the castle; she hasn't had the swordplay that everyone else seems to get," Coulby said. "But I'm hoping she can get more involved with the action in the future."