A Town Called Mercy. Review.

Speaking as someone who's only ever seen four Westerns all the way through, and one of them was Carry on Cowboy, I was always going to approach a Wild West themed episode of Doctor Who with the wariness of an ageing rattlesnake.

But, with the open-mindedness that's made me as big a legend on the plains as Calamity Jane, that didn't stop me sitting down to watch it.

A Town Called Mercy finds our heroes confronting a problem.

That problem's a cyborg gunslinger who wants the locals to hand over an alien who's living amongst them.

 Or else.

That alien is Kahler Jex who, since his arrival, has provided the town with a power supply and saved everyone from cholera, making him a valuable asset to the locals - especially to Ben Browder's Sheriff Isaac, a man determined to keep him alive and to maintain civic unity in the face of danger.

The moral choice seems simple until the Doctor discovers Jex is the war criminal responsible for creating the cyborg in the first place. Now the Doctor has to make a decision. Is it better to hand the man over to meet his death, or to let him live and escape the consequences of his actions?

It's not the first time the show's handled the dilemma in question. Christopher Eccleston was faced with exactly the same one way back in Boom Town. As in that episode, it provides the opportunity for soul-searching on the part of the Doctor, as well as plenty of talky bits. As in that one, the Doctor ultimately doesn't have to face up to the responsibility of making the decision.

This can only be viewed as a cop-out by writer Toby Whithouse but, given that Doctor Who's primarily designed to be family fare, the truth is it's difficult to see how it could ever respond to such a challenge without being forced to cop-out in some way.

Despite my fears before watching it, this is by far the best episode of this season so far, reminding us again that Doctor Who isn't Star Wars and nor is it a sit-com. Instead, it's at its best when it drops the silliness and loses all pretensions of epicness, in order to simply concentrate on telling a story about people.

I really don't have that much to say about A Town Called Mercy because there's really not much to criticise. Maybe Isaac's death failed to carry the emotional impact it was meant to, I could have done without the cyborg talking to itself as it stalked the town, and Karen Gillan didn't act as good as she looked but these are minor failings that did little to undermine the success of the outing.

Whithouse even solved the too-many-companions problem, by sidelining Rory to such a degree it was a genuine shock to me when he suddenly reappeared in a scene and reminded me he was actually in this week's episode.

It'd be nice to think every episode from now on could be as successful as this one but we all know we don't live in a perfect world and, like a drunken cowpoke, the show will as always lurch around from good to bad. Still, it can at least for this week ride off into the sunset, with its head high and its stetson proud, as we wait to see what awaits it over the next horizon.