- You may be looking for the short story of the same name.
Doing Time was the third story in the audio anthology, The Demons of Red Lodge and Other Stories, which comprised the one hundred and forty-second release in Big Finish's monthly range. It was written by William Gallagher and featured Peter Davison as the Fifth Doctor and Sarah Sutton as Nyssa.
Janson Hart is sentenced to do time for a crime and is thrown in a cell with a man named "Doctor John Smith" (the Doctor), who claims that he has been framed as someone else with the name has committed the crime he is being accused of on this planet, named Folly. He is offered a chance at parole if he admits his attempted sabotage but is refused by governor Chaplin. The Doctor reveals that he had come to stop an explosion that will take place in one year, having detected it in his TARDIS. They ignore him and put him in solitary confinement.
Nyssa, meanwhile, wonders through a town and attempts to get herself arrested but to no avail. Nyssa visits the Doctor in prison and discovers what he has been up to, and he, her. They later find out that governor Chaplin is running for president of the colony and when the inmates attempt an escape, she reveals her forceful and inhumane approach to swiftly stop it. The two are interrogated by her where she reveals she believes the Doctor about the imminent disaster but plans to use him and the situation to gain a political advantage to win the presidency of the colony. He refuses to help her and she orders him to be locked up in solitary. As he is locked up, Dask, the guard they made friends with earlier, delivers a secret message to him from Janson.
The Doctor survives five months of solitary confinement and is released to applause, simultaneously Nyssa is imprisoned by Chaplin after she reveals she has incriminating evidence of a conversation Nyssa had earlier with Janson, despite her interpreting the conversation differently. They discover that Jabreth's parents have come to pick im up, arriving in their ship to pick him up at the end of his sentence, coinciding with the day of the massive explosion, which the Doctor realises is the cause of the explosion due to the ship's drives, and that by warning the governor, who also knew the day the parents would arrive, she had put the two events together and planned accordingly. The governor attempts to trick the citizens into believing they are being assaulted by an external threat but the Doctor uses the time fields to stop her. The prisoners manage to escape and the Doctor and Nyssa prepare to leave. The Doctor explains that the captured Chaplin will be out of the time prison in a week, but by then, once word gets out that all the prisoners have escaped, her ratings will plummet. He also reveals that despite the fact some of them were entirely guilty of the crimes they committed, he hopes the therapy, advice and sports training he gave them while they were all imprisoned together will help them relax and better themselves and convince them to turn away from a life of crime.
- The Doctor - Peter Davison
- Nyssa - Sarah Sutton
- Janson Hart - John Dorney
- Governor Chaplin - Susan Kyd
- Dask / Judge / Jabreth / Hobbling Pete - Duncan Wisbey
- The Doctor organises a Twenty20 cricket tournament.
- Doctor John Smith is a "catch-all" name for all criminal offenders on planet Folly.
- Nyssa doesn't know who Bonnie and Clyde are.
- Nyssa is implied to have had a romantic interest in Dr. Michael from the colony's university hospital.
- Janson asks Nyssa what a Time Lord is.
- There are 1079 prisoners on the colony of planet Folly.
- Chaplin, when being entrapped by the Doctor, mentions he has a beard.
- The planet's name, "Folly", is a pun on the English word "folly".
- Nyssa refers to the Fosters on Traken. (TV: The Keeper of Traken)
- Nyssa tells the Doctor that she is learning a great deal about telebiogenesis. (TV: Castrovalva)
- The Doctor has a beard after waiting a year to save Chaplin using the time field. The Eleventh Doctor had one while being imprisoned in Area 51. (TV: Day of the Moon)
- Official Doing Time page at bigfinish.com
- DisContinuity for The Demons of Red Lodge and other stories at Tetrapyriarbus - The DisContinuity Guide