“Once Upon a Time” is introducing many new faces this season, but none is as important as Elliot Knight’s Merlin. The 25-year-old British actor is the latest addition to the ABC drama’s fifth season – and his character is Emma Swan’s (Jennifer Morrison) only hope at returning from the Darkness.

The hit fairytale series returned Sunday with its Season 5 premiere and shockingly introduced Merlin within the first five minutes. What some viewers may not have realized is that Merlin was the theater usher who approached young Emma while she was watching “The Sword in the Stone.”

“It was a scene they added in,” Knight told International Business Times. “It’s funny because a lot of people didn’t realize who it was – or at least they didn’t realize who they think it was. I find it so interesting because everyone had different ideas. Like, is it Merlin? Is it not? What’s happening?”

Knight was cast as Merlin on “Once Upon a Time” in July, just a couple months after the Season 4 finale aired. Although fans have yet to actually meet the character, the series already set Merlin up as potentially the biggest player in the Enchanted Forest. But don’t think for a second that Knight is intimidated by the powerful role. Despite many reincarnations of Merlin over the years, the actor is having fun making the character his own.

“For me it was never a case of trying to imitate something or some way that he’s been imagined,” he explained. “It was more about the context of the show. It was more about what happened at the end of Season 4 – what happens in the entire show in fact. It’s where they’re going and what they need to achieve, and making the character that best fit in with what’s going to be happening in Camelot.”

Bringing the character to life in the “Once Upon a Time” universe involved “highlighting and selecting” the best qualities about Merlin. But Knight can’t take all the credit for his portrayal. He said the show creators – Edward Kitsis and Adam Horowitz – and the writers really gave Merlin “human depths and dimensions.

“You don’t want to be just running around and doing magic for no reason,” he joked. “It makes it much more grounded.”

Although his role is a serious one – Merlin’s the only person that can save Emma – that doesn’t mean that Knight’s time on screen isn’t fun.

Once Upon a Time Emma Merlin (Elliot Knight, not pictured) is the only one who can save Emma (Jennifer Morrison, pictured) from the darkness on "Once Upon a Time." Photo: IBTimes

“The stakes are always high on the show,” he continued. “I think anyone who watches it knows that by now, every episode something drastic is happening. It’s interesting to be a character that has a little bit of license to have some freedom – in a sense – from the stakes and have a bit of play and a bit of fun with it, but at the same time being so heavily attached to what needs to be done.”

So, when will viewers see Merlin again? Knight can confirm that he’s appearing in episode 7. However,  fans should keep their eyes peeled before that.

“I don’t think he’s going to come up when people expect him to,” Knight teased. “He’s definitely got unpredictability to him. He will be in soon, people might have to wait for a little bit but he will pop up when they don’t think he will.”

It’s only a matter of time before “Once Upon a Time” fans get to really dive into the new character.

“He’s going to be mysterious,” the actor promised. “At least for a little while longer.”

Catch Elliot Knight on “Once Upon a Time” Season 5 when it airs on ABC on Sundays at 8 p.m. EDT.