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A Town Called Mercy was the third episode of series 7 of Doctor Who.

It was the first televised western since 1966's The Gunfighters. From a production standpoint, this story was notable for being the first episode of BBC Wales whose visual effects were not credited to The Mill. Instead, the credit was given to Space Digital.

The episode explored how war created consequences, particularly what happens to the survivors and those seeking revenge.


Missing Mexico by 200 miles, the Eleventh Doctor ends up in Mercy, Nevada, where something's not quite right... The locals are hostile to strangers, and a border of stone and wood surrounds the town. As the Doctor soon finds out, a gunslinger is behind this, and not just an ordinary one.


Against the backdrop of a starry night desert, an unseen woman with an American western accent narrates a story her great-grandmother told her when she was a girl... a story about a man who fell from the stars and was weighed down by the things he had seen, giving the impression it might be yet another legend about the Last of the Time Lords.

A cyborg known as the Gunslinger shoots down a probe in the middle of the desert while chasing Kahler-Mas. The cyborg tells his victim to make peace with his gods, to which Mas retorts that they are his as well. The Gunslinger says they are not his gods any more. Mas tries to pick up a piece of debris to defend himself, however, the cyborg knocks it away and prevents his target from moving. Pinned to the ground by the Gunslinger, Mas is resigned to his fate and asks his executioner if he's the last of the people he's hunting down. Before opening fire, the Gunslinger replies that there is just one more: "the doctor".


The Doctor, Amy and Rory draw attention upon entering the saloon

In the desert during the daytime, the Doctor, Amy and Rory examine the population number on the sign of a town called Mercy, seeing it has 81 inhabitants. There are several odd things about the town including a sign saying "KEEP OUT" and a strange stone and wood boundary line surrounding the town. According to a scan with the sonic screwdriver, it is just what it looks like, nothing else. The trio enter the town, unaware the Gunslinger is watching them.

Walking down the street, the trio notices no-one is outside; instead, the townsfolk are inside, giving them hostile stares. Even odder, however, is that the town is using electricity, which will not be discovered until about ten years later. Rory is not that concerned, as it's only a few years off; the Doctor jokes back at him that he said the same thing when he left his mobile phone charger behind in Henry VIII's ensuite. Because of all the odd events happening at once, the Doctor wonders if someone has been peeking at his Christmas list.

They enter the saloon, where the Doctor orders a drink. They're asked by the patrons who they are. As the Doctor introduces himself, Amy and Rory, everyone stands up; the Doctor is impressed with how polite they are. He then notices someone measuring him, stating he doesn't need a new suit; the man tells him he's the undertaker, not a tailor. One of the patrons asks if the Doctor is an alien. Surprised, the Doctor says that in his terms, they're the aliens, but in their terms, he is indeed an alien. The patrons get up from their seats and grab the three of them, dragging them to the edge of town.

They toss the Doctor outside the boundary and hold him at gunpoint to prevent him from coming back in; they hold Amy and Rory still to prevent them from helping the Doctor.

Gunpoint in Mercy

The Doctor is placed at gunpoint by Mercy locals.

A man spots the Gunslinger approaching and they prepare for the worst as the preacher says a prayer. At the last second, however, a shot is fired from the crowd. The town Marshal, Isaac, appears and tells the people to let the Doctor and his friends back in, pointing out the Doctor is not the one the Gunslinger wants. This is met with defiance from the crowd as the Doctor fits the description of who the Gunslinger demanded — an alien doctor. However, Isaac tells them that they know who the Gunslinger really wants, saying it's no reason to send the Doctor to his death. Isaac orders the Doctor to quickly get back inside the boundary. He does, and the Gunslinger departs, appearing angry.

Back in his office, Isaac explains to the travellers that the Gunslinger appeared three weeks ago, placing the boundary around the town and demanding they hand over the "Doctor". Though he hasn't killed anyone, he's stopped supplies and reinforcements entering, and the town is slowly starving to death as a result. When someone tried exiting the boundary, the Gunslinger shot at him, putting a hole through his Stetson. The Doctor believes the Gunslinger had poor aim, but Isaac points out that the hat was the target. This annoys the Doctor, who loves hats. Amy reminds the Doctor they were supposed to go to Mexico's Day of the Dead festival. The Doctor ignores her complaint, demanding the Gunslinger's real target; he knows that the Marshal's office would be the safest place to keep him if the townsfolk want to hand him over. Though Isaac protests, a voice tells him to stop putting on the act; it comes from the cell. A man pulls the blanket hiding him off and introduces himself as Kahler-Jex.

The Doctor is delighted to meet Jex explaining the Kahler are a race renowned for their technological expertise, saying they could create a spaceship "out of Tupperware and moss". Jex tells them that his ship crashed out in the desert some years ago. He was rescued by the townsfolk, who took him in. Since then, he became the town doctor. He cured an outbreak of cholera and used the remains of his ship to give the town electricity. The Doctor is curious why the Gunslinger is after him. Isaac interjects to defend Jex, saying Mercy is a town of second chances. He is also angry that the townsfolk are thinking of turning their friend over to the stranger. The Doctor decides to use the TARDIS to help Jex escape and evacuate the town, but first, they must engage in a little sleight of hand to get past the Gunslinger.

Grabbing the Stetson Isaac showed him, the Doctor borrows the Preacher's horse. The Preacher has named the horse Joshua, but the Doctor tells them that "[the horse is] called Susan, and he wants you to respect his life choices." He rides out to collect the TARDIS. In the meantime, Isaac, dressed in Jex's hat and coat, runs off along with Rory in another direction to buy time. The Gunslinger takes the bait and chases after the two men, but curiously holds back on firing when his systems warn of the high risk of hitting Rory. In town, Amy comforts Jex, who tells her that he knows she's a mother. Curious, Amy asks how he knows. Jex says it's because it's in her eyes: kindness, sorrow, and love. He goes on to say that he's something of a father himself.

In the desert, the Doctor finds the power cables from Jex's ship, with the horse protesting that he should stay on task. However, the Doctor is not one to give up on a mystery; he starts following the cords back to the source. Jex notices power fluctuations in the town, from the Doctor messing with the cords. Jex becomes worried that the Doctor isn't following their plan. Amy simply says, "Welcome to my world." The Gunslinger catches up to Rory and Isaac and pins them down behind a cliff face, having switched to heat-seeking vision to find them more easily.

The Doctor finds the Kahler ship hidden, but not damaged as Jex had claimed. After some effort, he manages to open it but trips the ship's alarm: alerting Jex and the Gunslinger, who breaks off his pursuit of the other two men. In town, Jex is panicking because the Doctor has gone against the plan. The Doctor enters the ship and manages to override the defence system. He asks the computer what it knows about the Gunslinger. Unfortunately, the ship does not understand the term, so the Doctor tries a different approach and asks it about its crew. His request brings up logs detailing horrific experiments conducted by Jex. The Doctor watches in silent shock, listening to Jex calmly detail the events as his victims scream in the background.

Back in Mercy, Amy finds herself staring down the barrel of a gun held by Jex. He assumes that the Doctor has learned some things about his past which the townsfolk won't understand or forgive. He is going to flee and take Amy with him as a hostage since the Gunslinger's programming forbids him from harming civilians unless the situation is extreme. Jex's escape is thwarted by the return of Rory and Isaac, who demand answers.

In Jex's Ship

The Doctor is caught inside Jex's ship.

In the desert, the Doctor leaves the ship and comes face to face with the Gunslinger, poised to attack. He manages to get the alien to stand down by revealing he knows what Jex did and he knows who the Gunslinger is. The cyborg lowers his weapon slightly. The Doctor has worked out that the Gunslinger is one of Jex's "test subjects". He pleads with him to spare the town and let Jex be brought to trial. The enraged cyborg refuses but reveals that he hasn't gone after Jex in the town because he doesn't want to harm the civilians who would likely get in the way. He leaves but warns the Doctor the next person who tries to leave the town will be killed unless the Kahler is handed over.

At the Marshal's office, Jex tries to wave off his actions as a moment of panic. The Doctor returns and accuses Jex of being a liar and murderer. He explains to Isaac, Amy and Rory that the Gunslinger is a cyborg created by Jex and a team of scientists. He goes on to explain that they took unsuspecting volunteers on the pretext of military training and experimented on them. Those that did not die were turned into weapons. Rather than deny his actions, Jex admits and even defends them, explaining Kahler suffered a devastating nine-year war which decimated half the planet. Kahler authority ordered their scientists to create weapons able to end the war, and they did. In a week, the cyborg army defeated the enemy before deactivating. However, the Gunslinger didn't deactivate. Jex guesses he was damaged in battle, restoring his original personality and allowing him to disregarded pre-programmed orders. Since then, he has hunted down and killed those responsible for turning him into a monster. Jex is the last one remaining.

The group is unsure of what to do. Rory believes that they should hand Jex over to the Gunslinger: he is a war criminal who deserves to pay for what he's done, and there is no reason why everyone in town should die for him. However, Amy and Isaac disagree with him. Isaac points out that Jex saved the town from cholera, while Amy doesn't believe it's their place to march a man to his execution. The Doctor struggles with the decision. Jex observes this and says that the Doctor could never make a hard choice like he had. This provokes the Doctor's fury, as he drags Jex to his feet and marches him outside. Rory attempts to stop Amy from interfering, pointing out that it is Jex or them, but Amy isn't willing to let the Doctor do what he's about to do.

The townspeople gather around as the Doctor pushes Jex over the boundary to face his surviving victim; he even points a gun at him, not knowing if he would use it or not. Amy stops the Doctor by also grabbing a gun, pointing out that this is not his way. The Doctor responds that every time he faces evil he tries to understand, and has even shown mercy to his enemies, such as the Master and the Daleks; however, each time, they've come back and killed again. For once, he is going to think of the victims and let Jex's victim get revenge. Disgusted, Amy tells the Doctor that this is what he becomes without any companions to hold back his dark side; she reminds him how they normally resolve these problems. The Doctor is persuaded, deciding that he cannot allow this; Jex needs to be persecuted, not killed in the Gunslinger's vengeful rampage.

Tek's desert Search

The Gunslinger offers one last chance to hand Jex over.

Before the Doctor can get Jex back over the boundary, the Gunslinger appears behind him ready to kill. The scientist addresses the cyborg by his original name Kahler-Tek; having remembered the names of all the test subjects. He pleads with Tek that he has changed, but the cyborg doesn't relent and opens fire. Isaac, however, steps in the path of the blast to save his friend. He is gravely wounded. With his last breath, he makes the Doctor the new Marshal and tells him to protect the town. A distraught Doctor sends Jex back to his cell ordering the townsfolk to keep him safe. He confronts Tek, saying this must end. The cyborg agrees and offers a final ultimatum; hand over Jex by noon tomorrow or everyone will be killed. As the Gunslinger departs, a shocked Amy exclaims that the Doctor is now the Marshal of the town; he retorts; "and you're the deputy."

Night comes, and the Doctor wonders what he should do, as the undertaker gives him a cup of coffee. If Isaac thought the Doctor was good enough to be Marshal, the undertaker has complete faith in him. However, he begins taking measurements again before the Doctor sends him away. The preacher comes into the Marshal's office and greets the Doctor, along with Amy and Rory. He tells them to come outside as there is a lynch mob arriving. On the preacher's suggestion, the Doctor grabs the gun and holster, putting them on. They go outside to greet the mob. They tell the Doctor that he should go for a walk; when he returns, Jex will be gone and he won't need to feel guilty. However, the Doctor tells them that it would betray the town's principles and Isaac's sacrifice. They again explain that they are only concerned for their families; a boy aims a gun at the Doctor. The Doctor asks him if he really has the courage to pull the trigger, eventually talking him and the mob down.

Once the mob leaves, the Doctor returns to the cells to talk with Jex, who also tries to goad him into handing him over to Tek. The Doctor tells him that he won't. Sensing how conflicted the Doctor is, Jex says it would be so much easier if he was just one thing, instead of two; the mad scientist or the benevolent doctor. Finding Jex's attempt to goad him amusing, the Doctor says it's a pretty clever idea on how to make up for all the lives that he took, being the town's doctor. However, it's not up to Jex to decide when his debt to society is paid. Jex then explains that he fears death. Kahler religion says that once he dies, he must climb a mountain, carrying the souls of all those whom he wronged in life; Jex cries that Isaac, his only friend in Mercy, will be added to his load. The Doctor slightly sympathises.


The Doctor at high noon.

Come noon the next day, the Doctor faces off with the Gunslinger in a duel instead of handing Jex over. Facing the cyborg with his sonic screwdriver, he uses it to produce a high-pitched frequency that shatters glass and disorients the Gunslinger. The Doctor takes advantage of his confusion and runs off, as the Gunslinger fires random shots. The townspeople, who had used make-up to copy Jex's facial marks that the Gunslinger uses to ID him, run about to cause confusion. As part of the Doctor's plan, Jex uses the confusion to escape town and head for his ship.

Back in town, the Gunslinger searches for Jex, breaking into the church and frightening the patrons. Catching sight of a scared little girl, the Gunslinger lowers his weapon and leaves. Tired of his automatic targeting falling for the Doctor's trick, the Gunslinger switches to manual, finding the Doctor hiding nearby. The Doctor tells him that Jex has gone, enraging the Gunslinger. Jex calls from his ship explaining that if he fled to another planet, the Gunslinger would follow him and put others in danger once more. Jex tries to make peace with Tek, asking him about his hometown and how sorry he is for the terrible things he did. Jex then activates his ship's self-destruct and kills himself, something the Gunslinger sees as honourable. Because the Gunslinger sees himself as nothing more than a weapon of war, he prepares to self-destruct a safe distance in the desert. However, the Doctor tells him that while he may have built as a weapon of war, he can now protect the peace instead.

Later, the Doctor has brought the TARDIS to Mercy to collect the electronics Jex left behind, not wanting to damage history. He asks Amy and Rory if they'd like to find out what happened to the monkeys and dogs that were sent into space during the 50s and 60s; apparently, they won't believe where the animals all ended up, which the Doctor finds amusing. However, Amy and Rory tell him it's time they went back home as their friends might start to notice that they age faster. He complies and they board the TARDIS. The Doctor tests to see if he can draw faster than someone before entering himself.

The woman narrates again, saying Mercy was already used to the strange and unexplainable; her great-grandmother was a little girl when this happened. The little girl from the church is seen walking off a short distance from the town, as the woman explains that Mercy has never had any kind of official law enforcer since then, but the residents never seem to worry as if they have a secret protector. The little girl looks off at a hill, where the Gunslinger is standing. Gazing into the distance, a close up of the Gunslinger shows that the Doctor has made him the new Marshal. Kahler-Tek smiles and begins his watch over the town of Mercy.


Uncredited cast[]


General production staff

Script department

Camera and lighting department

Art department

Costume department

Make-up and prosthetics



General post-production staff

Special and visual effects


Not every person who worked on this adventure was credited. The absence of a credit for a position doesn't necessarily mean the job wasn't required. The information above is based solely on observations of the actual end credits of the episodes as broadcast, and does not relay information from IMDB or other sources.

Uncredited crew[]

Space Digital[]


  • The Doctor mentions the Master and the Daleks when telling Amy why he is willing to let the Gunslinger take revenge on Kahler-Jex.
  • The Doctor mentions Henry VIII when he describes an incident where Rory left his mobile phone charger in Henry's suites on a previous adventure.
  • The Doctor rides a horse named Susan.
  • Kahler-Jex can tell that Amy is a mother.
  • The Sheriff of Mercy was not in town during this time.


  • 81 is mentioned.




  • While Toby Whithouse had never written a western before, he was a fan of the genre, in particualr The Dollars Trilogy and Deadwood. He sought to balance the classic tropes of the genre with the moral complexity of modern Westerns.
  • The Doctor's role as the reluctant defender of Kahler-Jex was inspired by To Kill a Mockingbird, in particular the scene with the mob at the jailhouse.

Story notes[]

  • Working titles for this story included The Gunslinger and Mercy.
  • This was the first televised Western episode since The Gunfighters in 1966.
A Town Called Mercy logo

The unique logo for A Town Called Mercy.

  • For this episode, the Doctor Who logo's texture had a wooden look with gunshots, representing the story's Western setting.
  • This was the first episode of the BBC Wales revival whose visual effects were not credited to The Mill. Although various episodes had, in the past, required help from other companies, The Mill had always managed to retain the main "Visual Effects" credit. The most notable recent example of this was The Doctor, the Widow and the Wardrobe [+]Steven Moffat, Doctor Who Christmas Special 2011 (BBC One, 2011)., where some of the effects were done by Space Digital. There, Space received an "Additional Visual Effects" credit. Here, however, they become the first company other than The Mill to get the main VFX credit since Rose [+]Russell T Davies, Doctor Who series 1 (BBC One, 2005)..
  • As is routine for post-2005 Doctor Who, a "NEXT TIME" trailer for the next episode was shown at the end of the episode.
  • The beginning of the title sequence shows lightning effects that are usually hidden by the final images of the episode teaser intro.
  • This is one of only two times the Master was mentioned in the Eleventh Doctor's televised era. The other time is The Time of the Doctor [+]Steven Moffat, Doctor Who Christmas Special 2013 (BBC One, 2013)..
  • This is the first episode to be written by Toby Whithouse to not include the theme of what happens after leaving the Doctor. It however does explore what happens when the Doctor travels alone for too long.
  • It was Matt Smith's idea for the Doctor to have a toothpick in his mouth before entering the saloon, as he wanted to look like a western hero.
  • Kahler-Tek was initially a robot, but quickly became a cyborg because Whithouse felt that this offered greater emotional depth.
  • Kahler-Tek was originally named Kahler-Tec.
  • Kahler-Tec and Kahler-Jex were originally recent arrivals on Earth, but Steven Moffat suggested that it would be more effective if Kahler-Jex had been residing in the fictional town of Mercy for an extended period of time, because it would give the residents a stronger motivation to defend him.
  • At an early stage, Whithouse considered killing off Kahler-Tek partway through the story, which would then focus on Kahler-Jex's villainy. This approach was soon inverted, with Kahler-Jex shot to death by Isaac's crazed father George, a character who would ultimately be dropped from the narrative. The drama of the final act was then generated by the cyborg's intention to punish the town that had deprived him of his revenge. The story climaxed with the Doctor confronting Kahler-Tek with the projected image of a woman named Kahler-San, who wore the same pendant as the cyborg. Although Kahler-Tec saw through the deception, it was enough to convince him to abandon his assault on the people of Mercy. Moffat felt that the script started to run out of steam following the death of Kahler-Jex. It was agreed that preserving both Kahler-Jex and Kahler-Tek through to the climax would give Whithouse more space to explore the moral grey areas of his scenario.
  • Originally, it was Rory who would argue for Kahler-Jex to be turned over to the Gunslinger. This was changed because Moffat was eager to embrace the notion of the Doctor becoming a less sympathetic figure when he was deprived of regular travelling companions.
  • The episode formed Block One of season seven alongside Dinosaurs on a Spaceship [+]Chris Chibnall, Doctor Who series 7 (BBC One, 2012)..
  • A major change made to the episode was the elimination of a hauntingly beautiful melody which accompanied the appearance of Kahler-Tek. Kahler-Jex would have revealed that he had played this music during the torturous operation which created a cyborg in order to drown out the subject's screams, and it had now been co-opted by Kahler-Tek.
  • Moffat was keen on putting Matt Smith in a Western setting, who he called one of the last people one would expect to replace Clint Eastwood.
  • Moffat advised Whithouse and the other writers to not watch The Gunfighters in preparation for writing the script, because they felt it was "really not very good" and "not exactly the jewel in the crown".
  • Whithouse felt obliged to include common Western tropes, such as the Doctor riding a horse and a face-off. He stated the hardest scene to write was where the Doctor is forced to use a gun; the Doctor is a pacifist and he would need "the right sort of emotional journey".
  • Whithouse preferred the cyborg villain to be three-dimensional and sympathetic, which would require it to have a "living consciousness" rather than simply be a "soulless automaton". He wanted its look to be reminiscent of Frankenstein's monster, and later called the design "fantastic".
  • It took about three and a half hours to apply all the makeup to Andrew Brooke. Due to the costume, Brooke had to act with just his left eye.
  • Ben Browder accepted his role because his children were fans of the series, and he also wanted to do a western.
  • Matt Smith praised Browder, who he said "[made] a good cowboy" with "that great drawl", and Adrian Scarborough, who he said "steals the whole episode".
  • Whithouse was "thrilled" with Browder's performance, as it was how he imagined the character.
  • Scott Bakula was offered the role of Isaac and wanted to take it, but he was unavailable.
  • While Matt Smith was allowed to try riding the horse, most of the action shown in the episode was done by his stuntman.
  • Murray Gold mimicked Western-style scores when creating the music for the episode.
  • Filming the episode in Spain was cheaper than constructing a set in the UK.


  • Overnight ratings: 6.6 million.
  • Final Ratings: 8.42 million.[3]
  • 556,000 watched the episode in Australia.

Filming locations[]

  • Mini Hollywood, Spain
  • Texas Hollywood, Spain


Production errors[]

If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.
  • When the Doctor first puts on the Marshal badge, he puts it on his lapel. Later on, it changes between the lapel and his breast pocket.
  • When the Doctor and the Ponds first arrive in Mercy, the Doctor notices a street lamp and the camera cuts to an overhead shot. In this shot, Amy can be seen turning around slowly, but when the camera cuts to a close-up shot of the gang, Amy is facing the front again and turns around again like in the overhead shot.
  • When the gunslinger passes by the chapel, he stops by a normal window. The view from inside the chapel shows him standing by the window, but the window is made from stained glass. However, when he shoots the window, the window pieces are normal glass.
  • At 14:07, a castle-looking structure can be seen in the background on a hill. This is most likely Tabernas Castle, close to the filming location for this episode.
  • At 11:37, a modern 50 star USA flag is flying. In 1870 it would have 37 stars.


Home video releases[]


Series 7, part 1 DVD cover.

DVD & Blu-ray releases[]

  • A Town Called Mercy, along with the rest of the first half of the series (episodes one through to five) was released as Series 7 Part One on DVD and Blu-ray in region 1/A on 13 November 2012, in region 2/B on 29 October 2012 and in region 4/B on 14 November 2012.
  • Also, this episode was released as part of the Complete Seventh Series boxset on DVD and Blu-ray in region 1/A on 24 September 2013, in region 2/B on 28 October 2013 and in region 4/B on 30 October 2013.

Digital releases[]

  • In the United Kingdom, this story is available on BBC iPlayer.

External links[]


  1. Mulkern, Patrick (21 October 2013). A Town Called Mercy ★★. RadioTimes. Retrieved on 29 October 2018.
  2. Failes, Ian (22 May 2013). Doctor Who: Stargate's adventures in time. fxguide. Retrieved on 20 November 2018.
  3. Doctor Who Ratings - UK final