Merlin star Bradley James says the BBC drama is about to get darker.
The popular series is returning for its fourth instalment on BBC One, with the 27-year-old actor back as Prince Arthur.
Bradley said: “People who were 12 when we first started are now 15. And 16-year-olds are coming to the end of their teens, so it allows you to push those boundaries and also to develop the characters.
“We’re really just dipping a toe in the water of the darkness of the actual Arthurian legend, because of our time slot.
“The legends are incredibly dark, quite twisted and messed up, so we’re pushing to do justice to the stories.”
The actor joked that the best part of his day was when he got to take off his heavy armour.
“It means I start floating round the room and have this light feeling in my shoulders, which I haven’t experienced since six o’clock in the morning,” he said.
“As cool as it looks, I’m always happy when it goes.”
Merlin 4 premieres on BBC One on Saturday, October 1.