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You may be looking for the castle or the German town.

Colditz was the twenty-fifth story in Big Finish's monthly range. It was written by Steve Lyons and featured Sylvester McCoy as the Seventh Doctor, Sophie Aldred as Ace and introduced Tracey Childs as Elizabeth Klein.

This featured two notable debuts - the Doctor Who debut of David Tennant in a role as a Nazi officer, four years before becoming the Tenth Doctor, as well as the debut of Tracey Childs as Elizabeth Klein, who later became the Seventh Doctor's companion nearly a decade later.

Publisher's summary[]

October 1944.

As World War Two draws towards its conclusion, a Nazi defeat begins to seem almost inevitable. But that might be about to change...

Two intruders are captured in the grounds of Colditz Castle, the most secure Prisoner of War camp in Germany.

At first, the guards think they're dealing with British spies. But the strangers arrived in an advanced travelling machine, the like of which they've never seen before.

With this "TARDIS" in their hands, the Third Reich might triumph after all...


Part 1[]

An anomaly in the Time Vortex forces the TARDIS to land on twentieth-century Earth, but it’s unclear where exactly. The Seventh Doctor and Ace find themselves in an oddly familiar castle courtyard. The Doctor realises where they are, but too late; they are apprehended by German soldiers, led by one Feldewebel Kurtz, and the Doctor is shot in the shoulder. They have arrived at the Nazi prison camp known as Oflag 4-C—Colditz Castle. Now they are prisoners, and the TARDIS is in the hands of the third Reich.

The camp brings out the other prisoners to watch Ace and the Doctor being taken in, under the watchful eyes of an officer, Hauptmann Julius Schäfer, and his prisoner friend Bill Gower. Ace gives Kurtz her real name, but refuses to show him any respect; the prisoners are impressed by Ace. Kurtz finds the explosives and supplies in her backpack, and takes it as further evidence that they are there to rescue prisoners; he is confounded by her CD player, but he takes it and her other possessions for study for the war effort. He sends Ace for delousing. Elsewhere, Schafer takes the Doctor into his custody, and warns him that he won’t be able to get proper medical care until morning. He also warns the Doctor that the camp commandant has taken an interest in the TARDIS after watching it materialise. The Doctor accepts the warning, but gets Schafer to promise to care for Ace. Kurtz arrives to report on Ace’s “amazing technology”, but is displeased to see Schafer caring for the Doctor. Schafer exposes Kurtz’s real issue: the lack of respect from the newcomers. He refuses to let Kurtz force Ace to strip naked for delousing. In retaliation, Kurtz keeps the “technology” secret, and returns to question Ace. Ace tries unsuccessfully to escape; he takes it as an attack, but opts not to shoot her, instead informing her that she owes him a favour now.

In the morning, as the prisoners report for roll call, the Doctor presents Schafer with the bullet, which worked its way out of his wound. Schafer sends him to the camp physician anyway, and warns him that the German High Command already knows about the TARDIS, and is sending a Gestapo soldier to torture its secrets out of the Doctor. The Doctor makes Schafer feel his double heartbeat, shocking the man badly; but Schafer insists on waiting for orders. Meanwhile, Ace joins the other prisoners for roll call, meals, and recreation, and meets Bill Gower, who assumes she is a valuable prisoner on a secret mission; he introduces her to another prominenter, or valuable prisoner, Timothy Wilkins. Ace mentions her escape attempt, and Gower explains that this prison exists specifically to hold prisoners who have already escaped elsewhere. No one has escaped for over a year. Kurtz goes to question the Doctor, but what becomes obvious is that he is being kept in the dark by his fellow officers. This feeds the man’s paranoia that he is unimportant. The Doctor plays on this fear and calls him a coward to provoke him, and Kurtz beats him. He is interrupted by the arrival of a woman named Klein, who takes charge of the Doctor and sends Kurtz to bring Ace. She knows the police box is a TARDIS, and demands the Doctor’s key, threatening to shoot Ace if he doesn’t surrender it.

Part 2[]

Tim Wilkins meets with Ace. He believes that Gower is withholding the truth—that escape plans are being made, but they only include those they favour. He intends to escape before the Nazis, who are being pushed back by the Allies, begin using the prominenter as bargaining chips. She is picked up by Kurtz, who takes her to the Doctor’s cell; the Doctor is trying to probe at Klein and find out how she knows what the TARDIS is. She knows there is no record of their existence in this year, therefore she ignores his questions, and orders Kurtz to shoot Ace. The Doctor surrenders the TARDIS key. Klein takes him to meet Schafer at the TARDIS; she orders Kurtz to kill Ace if the Doctor doesn’t cooperate. The Doctor tells Ace to work on Kurtz’s paranoia. At the TARDIS, he opens it for Klein and Schafer; overwhelmed, Schafer refuses to do any more, and leaves to make a report. Klein admits that she isn’t here for the TARDIS, but for the Doctor. Meanwhile, Ace starts to mock Kurtz, who has dismantled the CD player; she says that Klein will take credit for his work. He finds it hard to restrain himself, but manages it, and takes her to mealtime, where she sits with Wilkins. Gower joins them, and talks with Ace, who lets slip that the war will be over by next year. This persuades him to take her into his confidence. Tim cautiously agrees to create a distraction, allowing Gower to take Ace to view the prison’s weaknesses. Kurtz catches them in the kitchens, and strikes Ace, threatening to take out the favour she owes him. Ace shoves him, and he takes this as an assault, and drags her to solitary confinement.

Klein returns the Doctor to his cell under the pretence of waiting for his transfer papers; but he has picked her pocket, and obtained the real transfer papers, so he knows she is lying. He also obtained her identity papers, and knows they are forged; she is impersonating the Reich’s representative, who has yet to arrive. He destroys the papers, horrifying her, until her reveals that they were blank; he still has the real papers. He gives her the real papers, and orders her to hurry up, thus subtly establishing his power over the situation. She gets the Commandant to release the Doctor to her, in exchange for the TARDIS; on the way out of the castle, they pass Ace en route to solitary, and the Doctor assures Ace that he will be back. Ace’s situation, meanwhile, angers the captive British officers, who—via Gower—ask Schafer for help. He can’t directly countermand Kurtz, but he is able to get Ace released from solitary, though she is placed on a punishment detail. Ace learns that there is no official record of the Doctor or Klein existing. Fearing what the Doctor may give up for her sake, she goes to Wilkins and agrees to help him escape…if they go tonight instead of waiting. Meanwhile, Klein takes the Doctor into the forest, where she has another form of transport waiting…but an indentation in the ground reveals the truth. Her transportation is the Doctor’s TARDIS—coming from some point in the future—and it is missing.

Part 3[]

Klein now intends to take the version of the TARDIS that is in the castle. As the Doctor and Klein return to Colditz, he pieces the truth together. The TARDIS is lost to the Germans in this year, 1944, and retained by the Nazis until 1965, the year from which Klein hails. In that year, she finds its flight logs and figures out how to get it back to its last landing point, at which she uses it to travel here. She intended to capture the Doctor and force him to explain the workings of the machine. He insists that she has actually created a causal loop—that is, by taking his key, she caused the TARDIS to be lost to the Germans in the first place—and now she will make the paradox worse if she takes the earlier version of the TARDIS, preventing it from ever being in 1965. She doesn’t care; she insists she can correct it later, and that her companions in the Reich in 1965 can interrogate him for the necessary secrets.

With Tim Wilkins, Ace gets into the castle’s medical bay, where he has nearly sawed through the bars on the window. It’s the beginning of a plan, but needs more work to escape the guarded courtyard beyond. Gower catches them, and explains that this is why he won’t incorporate Wilkins into any plans; the man didn’t even set a lookout on the sickbay, indicating he doesn’t have what it takes to properly escape. Still, Ace insists she only needs to escape temporarily, to take away Klein’s leverage over the Doctor and allow him to outwit Klein. Gower agrees to help, even if it means taking Wilkins; Wilkins and Ace must fake food poisoning after the evening meal, so that they will be sent to the sickbay. However, before she can brief Wilkins on the plan, Kurtz arrives and sends Wilkins out so that he can deal with Ace. She is forced to claim food poisoning early; Kurtz allows her a small victory in seeing another officer regarding the poisoning, but assures her he will have his chance eventually.

Klein’s admission about the Reich in 1965 has cued the Doctor in to a problem. Klein, it seems, is from an alternate future, in which the Reich won the war, a future precipitated by his arrival here at Colditz. She isn’t actually German, just of German descent; she was born in Britain, but welcomed the Nazis, and was fortunate enough to have Aryan features and hair and a Germanic surname. She argues with him about the validity of her timeline, and about his own refusal to change certain aspects of history. She refuses to give him anything to work with, but does tell him that history records that Ace dies tonight in a botched escape attempt, betrayed by a co-conspirator. Having heard enough, he slips his cuffs and captures Klein, shackling her to a tree, and leaving the handcuff key in sight but out of reach. He returns to Colditz.

Gower threatens Schafer to get him to remove the guard from the sickbay that night. However, it’s for nothing, as Wilkins betrays the group to Kurtz, in exchange for being removed from the list of prominenter prisoners. Kurtz questions Schafer about removing the guard, but is unsatisfied by Schafer’s excuses, and watches the sickbay himself. Meanwhile, Gower puts on a fake German uniform, and insists on knocking out the sentry outside the window, but Ace insists on taking the risk instead, as Gower has more to lose. Tim is set to watch the second sentry, out of view of the window, and take him out when it’s clear. Later, Schafer meets Klein returning alone, and tells her that the Doctor was arrested in Leipzig while trying to steal a car, and will be returned in the morning. At the same time, the ill-fated escape is beginning. Tim backs out, and Kurtz arrives and intercepts Gower and Ace at the fence. He sends Gower to solitary, but prepares to shoot Ace.

Part 4[]

Ace name-drops Klein to stop Kurtz from shooting; killing her in direct defiance of Klein’s orders would destroy his career. He is angry, but returns Ace to solitary confinement. In the morning, when the Doctor arrives and learns of Ace’s survival, he knows that Klein’s future is changing; it may already have changed enough to eliminate her timeline. Klein decides to correct it by killing Ace, and orders Kurtz to do so as soon as possible. Meanwhile, Gower is in solitary, but Kurtz is overruled regarding Ace, and she is returned to her regular cell. She is confined there except for mealtimes. At mealtime she meets Wilkins, who is bragging about having backed out in a timely manner; she is not convinced, and accuses him of betraying her and Gower. Schafer stops the resulting disturbance and returns her to her cell, but Tim is left to the mercies of the angry prisoners. The Doctor is put in the cell beside Gower; when he learns that Gower’s window overlooks the courtyard, he passes a message via Gower to Ace. It contains information that Ace can pass to Kurtz at their next encounter, which exposes Klein as a traitor.

Kurtz checks Klein’s identity papers, which the Doctor has changed to more obviously expose their forged nature. Kurtz returns them without comment, but the Doctor knows he will verify them later, and act accordingly. Klein now has a deadline, and fears returning without the Doctor, as she took the TARDIS without permission from her superiors, and with the help of her assistant, Schmidt. The Doctor reminds her of the paradox she’s creating if she takes the earlier TARDIS, but she dismisses it; history already records that the Doctor escapes Colditz, only to return to Germany in 1955, and be subsequently shot and left for dead; she can use the TARDIS to locate her own version, then return the earlier version to the castle in 1955, and the paradox will be averted. She takes the Doctor to the command centre, but is intercepted by Kurtz, who tries to arrest her. Meanwhile the Commandant wants to question Ace and Gower, and sends Schafer for them. En route, Ace hears Tim in pain in his cell, and gloats over him, saying he got what he deserved for his betrayal; this prompts an outburst from Schafer, who is now cold toward Gower. They hear gunshots in the command centre between Klein and Kurtz, and the Doctor intercepts them as he escapes from Klein. He reveals that he has discovered it isn’t the TARDIS that changed history, but Ace’s CD player, which contains lasers that could be studied by the Reich. This led to early uranium refining, allowing the Reich to win the atomic race. Now they must recover the player before they can leave. Schafer tries to stop them, but gives up when the Doctor reminds him of what he saw inside the TARDIS. They search the command centre and recover the CD player.

Ace mentions how lucky they were. If Klein hadn't arrived, things would've turned out much worse. The Doctor is not so sure it was mere luck. He found Klein's mention of using the TARDIS flight logs odd, considering that the TARDIS doesn't have any flight logs. The Doctor theorises that he left Ace’s body and the CD player here, when he escaped. After departing in the TARDIS, he likely checked the console and realised his mistake. As he couldn't cross back on his own timestream, he had to come up with another way to correct the alteration to history. So, he returned to Germany in 1955, and allowed them to kill him and capture the TARDIS, but then regenerated into his next incarnation, and became the “Schmidt” who would work with Klein, manipulating her into travelling back to 1944. He would then have set the TARDIS to dematerialise after Klein arrived, preventing her from completing her plans.

With the CD player in hand, the Doctor and Ace prepare to leave. She uses her recovered Nitro-9 to cause a distraction, and head for the TARDIS, but Kurtz is waiting there. He says that Klein escaped in a car, but he knew they would come here. The Doctor assures Kurtz that the TARDIS is safe in the hands of the Allies, but it isn’t really Kurtz he’s talking to; it’s Schafer, who is listening. Schafer orders Kurtz to stand down, but Kurtz shoots him in the shoulder. Gower takes the opportunity to attack Kurtz, allowing the Doctor and Ace to enter the TARDIS; Kurtz breaks free and follows, but is caught in the closing inner doors. He shoots the console, which causes the ship to dematerialise, killing him gruesomely. Shaken, Gower promises to testify that Schafer did his duty, should it become necessary. After all, after a fashion, they are both prisoners here.

Meanwhile, aboard the TARDIS, Ace is also rattled by her experiences, and by Kurtz’s death. While she may not be responsible for that, she has some guilt toward Wilkins, who was beaten. Although the timeline is restored, Klein is still at large, with dangerous knowledge. Ace decides she needs to grow up, and she’ll start with her name…Ace is young and childish, but Dorothy McShane will be more mature.



The Doctor[]

  • The Doctor is shot in the shoulder. The bullet works its way out of his body overnight.
    25 Colditz.jpg


  • Ace refers to the Stone Roses.


  • When the Doctor and Ace arrive, they are shouted at in German.



  • The character Feldwebel Kurtz is played by David Tennant, who portrayed the Tenth Doctor in Doctor Who from 2005 to 2010. This was the first time that he had a role in Doctor Who in any medium; he would play a number of roles for Big Finish before eventually landing his role as the Doctor in 2005.
  • The character of Elizabeth Klein returns as a companion-cum-ally in adversity to the Seventh Doctor in the audio story A Thousand Tiny Wings.
  • It is unknown to what extent Klein's erasure from the timeline in the audio story The Architects of History altered the events of this story. It was briefly mentioned by the new version of Klein that the Doctor had visited Colditz Castle in 1944, but his experiences there must have been substantially different due to the absence of the original Dr. Klein.
  • This audio drama was recorded on 26 and 27 May 2001 at the Moat Studios.
  • This story was originally released on CD. It is now available as a download only.


External links[]