Peacemaker.

TV Considering he has a space and time ship, the Doctor has opened the TARDIS doors in the old wild west surprisingly little. There’s only really been the 60s story The Gunfighters, what would now be described as a celebrity historical in which the then crew were mixed up with the gunfight at the OK Coral (referenced herein as the reason for the time lord’s reluctance to pay the era a visit) and a smattering of short stories, particularly Lance Parkin & Mark Clapham’s A Town Called Eternity from the BBC anthology Short Trips and Sidesteps which was more Wild Wild West than High Noon.

But then science fiction and westerns have never tended to mix that overtly, never quite working out how to balance the recipe – you either copy the tropes of the genre but not the icons (Star Wars) or appropriate them and make them a twist (Westworld). Only really Joss Whedon's Firefly has got it completely right, at least in its television incarnation; the film Serenity went more in the space opera direction apparently because the studio noted that the public might not be too comfortable with seeing these two genres existing side-by-side (even though the sight of a spaceship scaring the hell out of horses in a desert is rather nifty).

James Swallow’s Peacemaker hopes to redress the balance and for the most part succeeds, mixing the tropes of the western genre into the Doctor Who horse trough and although predictably in the end the phasers outgun colt 45s there’s enough here to convince you that a television revisit would not be an unappalling idea. The Doctor and Martha roll into the town of Redwater, Colorado just as its getting over the effects of a small pox epidemic, apparently cured by a travelling flim flam man with clearly no medical training and a medicine which obviously isn’t. Not long afterwards two outlaws enter town with murderous intent looking for the fake medic and all hell breaks loose.

As well as a range of Star Trek novels and a few Big Finish short stories, Swallow also has the Sundowners series of steampunk western novels in his holster so he's comfortable in this cross genre teritory. Clearly and rightly one of the author's main influences in Back To The Future III, with the appearance of a Mary Steenburgen-like teacher and this Doc getting on the wrong side of the local gambler and said outlaws.

As with that film, all of the characters feel as though they’re passing through from a western movie or novel, rather than the actual period in history which is understandable given the audience for the book (and indeed when it’s suggested that they visit Deadwood, the Doctor remarks that it’s a bit rude). If anything the author seems a bit more comfortable in these earlier scene setting chapters, and the reader gets a great sense of the town and its people, particularly said teacher Jenny, a rich invention whose a romantic potential might have flourished even more given a greater word length.

It’s a pity then that as the book goes on and the science fiction begins to intrude that the story becomes more derivative with many of the repetitive elements we’ve seen from the new series making an appearance. To describe what they are would perhaps spoil one or two of the few surprises, except to say that what’s done as a money saving measure on screen needn’t happen quite so much in the prose versions. Unless Swallow is making some meta-reference to how genre works tend to be pretty lacking in originality anyway.

That said, he nails this alien presence which is particularly epic and creepy, especially because of their knowledge of who the Doctor is and what’s he’s capable of if pushed. The concluding battle of wits takes full advantage of being in prose and would be really difficult to recreate on film without resorting the kind of thing some us endured during the Star Trek: The Next Generation episode Night Terrors. They really bring out the lonely god's potential darkness and we even learn a bit more about what he was like during the time war, the suggestion being that he deliberately tossed out some of his fundamental beliefs in order to claim victory something hinted at but never confirmed before.

Despite all of this, the book is always entertaining. The central relationship is brilliantly captured (on his own website he says 'I really liked the chemistry between David Tennant's manic-dynamic Doctor and the competent and smart Martha Jones' and this is one of those rare occasions in the spin-off fiction that the story feels part of the tissue of the television programme, with some of the concerns of the third series making an appearance including Martha’s mother’s Saxon fueled disapproval of their friendship, the unrequited love she has for the time lord and her building confidence.

Most of the major monsters are name-checked and it’s because she’s been able to face down the Daleks and The Family of Blood that she’s able to do some of the things she does here. If the Doctor just now and then becomes a bit generic, most of the time he’s very much the Tennant model, jumping about, repeat repeat repeating words and phrases and dropping pop culture references. But significantly in a charming rather than annoying way, which again is something other authors have never seemed to get quite right. It’s this duo and their infectious humour which ultimately makes the novel so engaging and one of the best of spin-off range so far.

Peacemaker, by James Swallow, is released by BBC Books on 26 December. ISBN 9781846073496.