Look out for a terrific guest turn from Farscape and Stargate SG-1 star Ben Browder in this fun-packed 45 minutes, as well as plenty of Old West action! And if you want to know more, check out our ten (relatively spoiler-free) hints below...
Doctor Who continues this Saturday (September 15) on BBC One and BBC America.
> Doctor Who: 'A Town Called Mercy' new pictures - gallery
> Doctor Who writer Toby Whithouse: 'Ben Browder is fantastic'
1. Worried about the Doctor leaving Solomon to die last week? His new ruthless nature is addressed here...
2. "Look at this - it's a load of ****** and lumps of ****."
3. Pay close attention, fact fans - the Doctor mentions his age.
4. "Oy! Don't swear!"
5. Our Time Lord hero doesn't just speak baby…
6. "Why would he want to **** you… unless he's *** you?"
7. 'Mercy' features, in our opinion, one of Murray Gold's best musical scores in a while.
8. "We're like buses!"
9. Garrick Hagon - Biggs out of Star Wars - has a small but fun role.
10. "Give me a Dalek any day!"
Are you excited for 'A Town Called Mercy'? Let us know below!