Tea – but the strong stuff. Leave the bag in.

Steven Moffat had promised that this initial run of episodes leading up to the Ponds’ departure would be like watching a different movie every week, and Mercy offers up two familiar tropes for us to enjoy. Firstly there are nods to just about every spaghetti western ever made. Filmed on location in Spain, the episode makes extensive use of both existing standing sets and the surrounding terrain and looks correspondingly epic. Murray Gold’s musical score echoes many of the classic western compositions produced by the likes of Ennio Morricone. And Toby Whithouse‘s script includes nods to many western staples, not least the final confrontation at high noon.

Secondly, of course, there is the cyborg Gunslinger, who could only have been a more direct nod to The Terminator if he had spoken with an Austrian accent. Initially portrayed as a relentless killing machine, as the episode progresses we are introduced to his strong sense of morality – he will not risk killing innocents – and he ends up serving as the town’s marshal, repaying the debt he accrued by inadvertently killing Isaac. Less Terminator and more a cross between Terminator 2 and Robocop.

A clean shot, but wide of the mark

Why would he want to kill you? Unless he’s met you …

All this set-up is stirring stuff, designed to please both children and the children within their parents. There’s plenty of fun to sit alongside a more heavyweight morality tale, and one which harks neatly back to the Doctor’s treatment of Solomon at the end of Dinosaurs on a Spaceship. But somehow, despite some pleasing moments and a strong opening half, it just didn’t quite come together for me.

A big part of this originates from a lacklustre script from Whithouse, whose previous Who efforts have ranged from the brilliant (The God Complex) to the dire (Vampires of Venice) via the mediocre (School Reunion). It starts off well, in particular capturing the essence of Matt Smith‘s bumbling, goofball Doctor perfectly early on. But beyond the first 15 minutes it starts to fall apart.

Firstly there is the central conceit around which the episode is based. The Gunslinger built the ring around the town so that no one could get in or out, although clearly he could cross the line whenever he saw fit. And he didn’t want to put innocent lives at risk. But would it really have been that difficult for him to teleport into and around town during the dead of night, locate Jex and execute him without risking innocent life? Of course, if that had been the case, the Doctor and his friends’ visit to Mercy would have been a short and pointless one as Jex would have been long since dead.

This is not how we roll.

Also, if these last few episodes are meant to be Amy and Rory’s grand farewell tour, why do they spend most of this episode sidelined? (And why is big-name guest-star Ben Browder so criminally underused?) Yes, Rory gets to run around bit playing hide-and-seek with the Gunslinger and Amy talks the Doctor down from the ledge, so to speak, and convinces him to protect rather than sentence Jex. But for the most part they’re left watching from the sidelines and we don’t really learn anything new about them. Except for Rory and Amy’s dispute. Amy won’t let the Doctor take the easy way out by sacrificing Jex, whereas Rory is all too willing to play the pragmatist and allow the safety of the many to outweigh the fate of the one. Was it just me, or did this just feel wrong for Rory? Yes, behind the mild-mannered nurse lies the Last Centurion, but this felt surprisingly cold.

And then there’s the Doctor’s face-off with Jex. Yes, I get it. As Jex says, it’s “like looking into a mirror”. They’re both alien doctors. They both had to take a big step into a moral grey area in order to end a major war. As a result, both carry a heavy burden. And some see them as a hero, while to others they are tyrannical war criminals. Their exchange reveals the inner demons the Doctor carries around with him everywhere, but this is territory we have covered many, many times in Who‘s history. (More subtle is the parallel that both are liars, as the Doctor warns his friends that “everything he says – it’s all lies”, echoing River’s “The Doctor lies” from Let’s Kill Hitler.) It’s a fair point but it’s all laid on rather heavy-handedly and I’m not sure it really adds anything to the plot. Unless …

The ending. I’m in two minds about how to consider Jex’s self-sacrifice. Taken in the context of this episode alone, it fell flat for me: predictable and overly drawn-out. But I wonder if what we saw was a prelude to the Doctor having to face up to his own demons and making a similar sacrifice himself, not to save others in the manner of David Tennant’s Tenth Doctor, but to atone for his deeds in the Time War and other tragic events. After all, Jex’s parting words are dripping with portent:

I have to face the souls of those I’ve wronged.

Is this perhaps the ultimate fate of the Eleventh Doctor?