After a promising premiere, Merlin falls back into some bad habits with this follow-up.

The veil between the worlds of the living and the dead had been severed at the hands of Morgana, unstoppable shades stalked the nights, killing all they came into contact with, and Merlin, accompanying Arthur with the intention of sacrificing himself in the prince’s stead, appeared to have been killed by the otherworldly Dorocha in the opening story.

In a twist that I’m sure will stun viewers across the nation, Merlin wasn’t killed at the end of the last episode, but is on the brink of death. Arthur (Bradley James) is insistent on abandoning his quest in order to take Merlin back to Gaius in order to save his life, a questionable decision considering the fact that Gaius’ strategy for dealing with the effect of the Dorocha is simply to line up the corpses of their victims and cover them with blankets – but hey, at least Merlin’s corpse will be warm.

The main problem with this episode is that the majority of its run time is taken up by sequences and side-stories that have little bearing on any of the plot developments in last week’s episode. When the denouement finally arrives, its emotional and dramatic impact is stifled by what viewers already know about the legend, and indeed, what’s coming up this series.

Meanwhile, the Dorocha, whilst still a reasonably effective enemy, basically just charge at the main characters like they did in last week’s episode and aren’t expanded in any way. A subplot involving Guinevere and Agravaine allows Angel Coulby to showcase her acting prowess, but ultimately has little relevance to the overall story.

However, John Hurt’s return as the voice of Kilgharrah is a welcome distraction, as are the scenes between Agravaine and Morgana, despite their infrequency. Gemma Jones (Spooks) is also fantastically menacing as the Cailleach, overcoming some slightly hammy writing to make a real impression in her limited screentime.

It’s by no means a poor episode of Merlin – there’s a lot of good mixed in with the bad – but we’d just held high hopes that some of the lazy writing endemic to previous years had been ironed out, which seemed likely after last week’s excellent opener.

If deus ex machinas, smelly feet jokes and the worst assassination attempt ever are what you’re looking for in the concluding part of The Darkest Hour, you won’t be disappointed by Saturday’s instalment. Everyone else on the other hand might not find the satisfying conclusion that they’re hoping for to what was otherwise such a promising central conceit.

Airs at 8.05pm on Saturday 8th October 2011 on BBC One.

> Order the Series 4 Volume 1 DVD on Amazon.

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