This Saturday, the Doctor, Amy and Rory will venture to the Old West to face off against a nasty cyborg villain in what looks set to be a corker of an episode.

It’s not only the plot and the sheer fun of the episode that’s getting us all excited however; it also marks the return of the superbly talented Toby Whithouse as an episode writer in his fourth script for Doctor Who and his third for Matt Smith as the Eleventh Doctor.

SFX Magazine caught up with him to have a quick chat about A Town Called Mercy and all the good things that we can expect from it, here’s a few interesting things that we learned whilst reading through the interview:

• The big movie tagline ideas that the first five episodes have been structured by may not continue in the 2013 run of episodes.
• Toby Whithouse is a huge Clint Eastwood fan.
• Guest star Ben Browder (Farscape, Stargate) has rather beautiful innate nobility which he managed to convey when filming.
• The Cyborg in the episode (Face me!) may have one or two moral surprises up his sleeve for the Doctor.
• The Doctor is forced to use a gun at one point, something that went through a lot of drafts to get right.
• Whithouse has written the Doctor as slightly more volatile and unpredictable now that he travels alone.
• Either Steven Moffat or Mark Gatiss advised Whithouse not to bother watching 1966’s First Doctor story The Gunfighters as it wasn’t exactly essential Doctor Who (nor would it have added much to the plot for A Town Called Mercy).

So there’s a few interesting facts for you to digest but if you want to read the full interview, it’s available via SFX’s website.

A Town Called Mercy will air this Saturday 15^th September at 7.35pm on BBC One, BBC HD and 9/8c on BBC America.