Up until now, Merlin has been Arthur’s faithful servant and friend, but that looks set to change when Series 5 returns later this year. “Their relationship definitely becomes a lot more strained, I think, because Arthur is the King now, Guinevere is the Queen,” reveals actor Colin Morgan (Merlin). “We are seeing Gwen becoming a real source of influence on him, and we see that become a real rock-steady duo.”

He explained that part of Gwen (Angel Coulby)’s role will be reminding Arthur (Bradley James) that he shouldn’t be galloping off on his horse at the first sign of a mission anymore; he must rule Camelot. That won’t stop Merlin from leading him astray, though…

“Merlin is an influence on him, but in a completely different way, in the way that he is so much in the know about how things should be,” Morgan continues. “But magic is a huge blockade. Their relationship is kind of what it’s always been, but something’s changed. They have put us in situations that are the toughest we’ve ever faced, but there is still room for what we’ve always had, which is a bit of banter.”

Merlin returns to BBC One later this year. Merlin Series 4 is available on DVD for £15.34 and on Blu-ray for xxx from Amazon.co.uk.