Camelot’s getting ready for a wedding: Arthur’s! Does this mean an episode without black magic (unless they’re the chocolates the lady loves…), loads of sword swinging and Merlin keeping his bright eyes on dimmer switch? Hardly. There’s not much entertainment to be had just from a chaste maiden fluttering her eyelashes at a dashing Prince.

The first problem is that the lady who Arthur is being pushed by King Uther to accept in an arranged marriage is Princess Elena (Georgia King – Little Dorrit, Jane Eyre). She’s a bit of a looker but she isn’t Gwen. And we all know Gwen is destined to become Arthur’s wife, even if they don’t know it yet. We’ve seen them slowly falling in love and enjoyed Arthur behaving like a doofus around her. He just hasn’t yet grown brave enough to toss protocol aside and announce that he is going to marry a commoner.

So, how can Arthur marry Elena? Merlin doesn’t think he should – and not just because of Gwen. Elena isn’t quite the catch she appears to be. Merlin suspects there’s bad magic at work and it stems from Elena’s nanny, who is really a pesky pixie. So he has to work fast and flash his eyes to protect Camelot and prevent Arthur from saying ‘I do’ when he should really be saying ‘I don’t’.