This morning, Merlin stars Colin Morgan and Alexander Vlahos (Mordred) appeared on BBC One’s Breakfast show to promote series 5. No spoilers!

In the interview, Vlahos is also asked about whether Mordred is a good or a bad guy, and his answer is intriguing. He says, “I suppose people think of Mordred as a bad character, but in episode three he got knighted in Camelot, he’s now a knight of the Round Table, so who knows?” Because of what we know of Mordred though, everyone is expecting him to turn at every second. “He’s come from the dark side and sort of made his way into the good, but I think people are still dubious about where his allegiances lie,” Vlahos admits.

Morgan adds, “This guy is the biggest threat there’s ever been to Merlin and his destiny, and it’s now about how Merlin overcomes that whenever the biggest threat he’s ever faced is right there, right at the right-hand side of the king, in Camelot.”

They go on to talk about the banter between Merlin and Arthur, and Morgan talks about the relaxed relationships and friendships between a lot of the characters on the show. But of course, in series 5 it’s all getting darker! Vlahos talks about how the show is acknowledging that the fans that started watching in series 1 are now a lot older, and this allows them to tell darker stories. This is more fun, Morgan explains, and also feels more true to the Arthurian legends themselves. “We go right down the road of where the legends are supposed to go,” he teases.

One of the presenters makes a joke about the characters putting on the “voices of doom,” which gets a big laugh out of Vlahos (guess he’s seen/done a few of those!), and Vlahos also talks about the relationship between the cast and crew and how the banter between Colin and Bradley and the knights continues off-screen as well.

And finally the presenters want to know if there will be more Merlin, and Morgan gives an ominous tease: “You know, whether there’s life in the stories and life in the characters, and whether that’s a life that’s gonna be lived further, or not, you’ll see very soon.” Well, that kind of sounds like someone’s dying, doesn’t it?! Maybe Arthur? Or… Gwen? Your guess is as good as ours!

Merlin airs tomorrow night at 20:20 GMT on BBC One!