The last time the Doctor strode through a wild west town he was William Hartnell, and he had toothache.

Now, 46 years later, the Time Lord dons his Stetson and returns to frontier America, and the last thing he’s worried about is his choppers.

A Christmas toy mask in the making stalks the desert around the beleaguered Milkybar Kid town of Mercy, a place where ‘ayveryone hays ayn Aymericun ayack-sent’ and some of the actors lay it on more noticeably thick than others. Only Ben Browder, excellent as the noble but weary Sheriff and likely to cause a ‘frelling’ pang in the hearts of Farscape fans everywhere, feels like he’s actually part of the scenery.

Cue the Doctor: the archetypal Wild West hero for all of time and space. A screwdriver-slinging Man With No Name, riding into town to beat the bad guys before disappearing into the sunset.

But in counterpoint to the usual Western tale of white hats vs black hats, Toby Whithouse has created a moral grey quicksand to burden the Doctor.

It’s a plot you can’t help but feel you’ve seen before (if you’ve watched a lot of Star Trek then this feeling will be amplified tenfold) but you can’t rightly place exactly where. This is where A Town Called Mercy falters; it feels too much like something that could have appeared/has appeared in any sci-fi show across the past 40 years.

However, it does allow Whithouse to explore the Western motif of a man seeking vengeance, and this brings the best out of Matt Smith in a way we don’t usually experience. Rarely do we see the Doctor get frighteningly angry, but here he’s oddly furious, and there are even shades of David Tennant’s ‘Time Lord victorious’ in the colder notes of his performance. In an otherwise forgettable script it holds your attention simply to see how our Doctor will deliver his brand of law in an otherwise lawless setting.

Visually it’s a gorgeous episode, as the use of the Oasys Theme Park in Almeria, filming location for hundreds of Westerns including The Good, the Bad & the Ugly, gives a Hollywood depth rarely seen on the show.

Topping off the dustball atmosphere in fitting style is the lush score of Murray Gold: a man who can never get enough credit for his work on Doctor Who. It’s a great Spaghetti Western soundtrack (or should that be Paella Western, given that this episode was shot in Spain?) that’ll remind older fans of the days of Morricone scores, Cinerama movies, and John Wayne telling you to eat your beans.

Aesthetics aren’t everything, however, and certainly not enough to keep the kids from getting fidgety. Against a dramatic backdrop there’s a distinct lack of drama, and you may find it hard to keep your remote holstered. This isn’t going to be anyone’s favourite episode of Doctor Who by a long-shot and after two excellent episodes the underwhelming feeling that Mercy brings is exacerbated.

At least you know the Doc will be riding back into town next week to save Saturday night telly.

Airs at 7.35pm on Saturday 15th September 2012 on BBC One.

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