Arthur finally claiming his seat on the throne of Camelot in last week’s exceptional episode, The Wicked Day, was undoubtedly the most iconic and pivotal scene from the Arthurian legend so far realised in Merlin.

It threw up so many exciting implications for the series going forward that we simply couldn’t wait for the show’s next instalment. Would Arthur and Guinevere finally get married? Would magic still be a crime punishable by death? If not, would Morgana still want to destroy Camelot?

The first episode of this brand new era of Merlin could have explored any of the aforementioned quandaries and been a hugely engaging piece of drama, but instead Aithusa focuses on a wholly uninvolving plot regarding a dragon egg and a rather bland character we’ve never met before called Julius Borden. Apart from a few passing references to Arthur’s new monarchic status, this episode could realistically have been placed anywhere within the last two years of the Merlin canon without any major continuity problems.

Aithusa’s complete ignorance of the ongoing plot would have been less difficult to swallow if the episode had been a strong standalone entry – you didn’t hear many Doctor Who fans complaining that The Doctor’s Wife, The Girl Who Waited or The God Complex hardly dealt with the show’s ongoing arc – but Aithusa is simply a by-the-numbers, formulaic romp which, whilst entertaining enough in parts, ultimately feels like what it is: filler.

Let us be clear; this is by no means the worst episode of Merlin ever. Some of the Indiana Jones-inspired sequences towards the end of the episode are pleasingly executed and it’s nice to see the Knights of Camelot having more involvement in the story, even if the comedic scenes they share with Merlin are slighlty hit and miss.

However, viewers just aren’t given a good enough reason to care about the plight of the dragons, meaning it’s difficult to invest emotionally in the episode at all, while the primary villain of the piece, Julius Borden, does little to inspire.

The birth of a white dragon at the end of the episode may well have ramifications in subsequent episodes, in which case maybe Aithusa isn’t as poorly conceived as it currently seems, but regardless, would it not have made more sense for this to be the third episode of the series instead of The Wicked Day? Why introduce such a game-changing plot development in one episode, only to all but completely ignore it in the next?

Nevertheless, next week’s episode looks set to remedy all the issues we had with Aithusa, so at least we have that to look forward to.

Aired at 8.15pm on Saturday 21st October 2011 on BBC One.

> Order the Series 4 Volume 1 DVD on Amazon.

What did you think of the episode? Let us know below…