The Eighth Piece (audio story)

 was the second story in the audio anthology Doom Coalition 3, produced by Big Finish Productions. It was written by Matt Fitton and featured Paul McGann as the Eighth Doctor, Nicola Walker as Liv Chenka, Hattie Morahan as Helen Sinclair and Alex Kingston as River Song.

Publisher's summary
15th century Prague: in the castle dungeons, a prisoner raves about the end of the world. Outside, Liv Chenka seeks out the workshop of a strange Clockmaker to see what he is creating.

England, 1538: Lord Thomas Cromwell finds his duties interrupted by otherworldly forces – clockwork soldiers, an unusual nun, and a mysterious scholar calling himself "the Doctor". Perhaps the truth can be extracted in the torture chamber of London's Bloody Tower?

Rome, 2016: Helen Sinclair has an appointment with an enigmatic Professor, whose greatest work is almost complete. Only the Eighth Piece is missing...

Plot
Osm hears the ticking of a Solver from his cell and begs for peace, saying that he is a good man. When the Clocksmith, Osm insists that he is not "one of [him]", but he ignores him and hurts him, not allowed to kill him. Osm says that everyone must know that the end is coming and the Clocksmith has him gagged, saying that it is time to complete his masterpiece and begin the countdown to doomsday.

After leaving Helen in Rome 2016, the Eighth Doctor takes Liv to Prague in the early 15th century, having run his sonic screwdriver's remains through the TARDIS and located temporal anomalies. The Doctor gives Liv a rundown of their separate missions and tells her that any further clock mechanisms that they find should only be moved by him, an explanation that is watched from below by a gagged Osm. Osm is visited by Apolena, who ungags him and gives him broth to eat before asking him to tell one of her stories to help him.

In England 1538, Abbot Malvern is forced to give riches over to Thomas Cromwell for King Henry VIII and is found withholding a ticking cog that recently came into the hands of the order. Cromwell finds Brother Octavian, whom Abbot Malvern says came to them disturbed, eavesdropping on them and says that he, a poor penitent, is how the religious should be. He threatens Abbot Malvern with early retirement and leaves.

Abbot Malvern attempts to comfort Brother Octavian, who hears what he calls devils and says to himself that he is a good man. The Doctor arrives, startling Brother Octavian and making him run away, and asks Abbot Malvern if he has any mysterious relics lying around. On the road, Cromwell is stopped by Solvers and his companion, Fothergill, is killed after being told to give them "the piece". River appears and saves Cromwell by shooting the Solvers.

In Rome 2016, Helen is saved from walking into the road by a Mr Whitman, who tells her that it will soon be the end of all worlds before they are separated by a group of nuns. She finds Rosalia, who works at the museum and is expecting her.

River, dressed as a nun and going by "Sister Cantica", defends Cromwell from the Solvers. The Solvers search through the party's chests and find the cog before folding in on themselves and teleporting away, leaving only one, which River had defeated, behind. Using her sonic screwdriver, she identifies the teleport as a short-range transmat and heads to the monastery.

Liv is approached by Apolena, who asks if she is lost and invites her into the castle kitchens to get warm. Apolena tells her about Osm, a harmless prisoner locked up the duke by request of a merchant called the Clocksmith, and his stories about the forest which she agrees to show to Liv.

At the monastery, Brother Octavian sees the Doctor visit the monastery and learn from Abbot Malvern about the cog taken by Cromwell. The Doctor buys a horse and heads off in pursuit. Brother Octavian tells Abbot Malvern that the voices know the Doctor and that he must not be allowed to interfere, saying that it is heresy. Abbot Malvern goes to warn the Doctor, who ignores him and rushes away, and speaks briefly with River before she uses her vortex manipulator to disappear. Brother Octavian wonders if the Doctor should build the clock or not.

Rosalia shows Helen around the museum, which she tells her is the first time that the professor has allowed somebody to see the special exhibit.

The Doctor reaches Cromwell and witnesses the Solver reawaken and transmat away after telling him that the answers to his questions are not for him. He says that he is surprised that the Solvers really exist, having believed them to exist solely in fairy tales, and hears of Sister Cantica from Thomas. The Doctor gives him his horse in return for being dropped back off at the monastery, but Cromwell tells his driver to head for London.

Helen looks at the collection, which she finds extraordinary. Rosalio goes to make her tea and to tell Professor Salvatore that she has arrived.

In the carriage, Cromwell tells the Doctor about the papists belief in a clock that counts down to the apocalypse which was disassembled as soon as it was made, believing that any man who had that knowledge would go mad. Whilst Cromwell does not believe in this clock, he wishes to keep it from the papists. The Doctor realises that they are on the way to London.

Rosalio returns to Helen with tea and tells her that Professor Salvatore has been delayed, but that she can wait in the special exhibit. Helen puts her camera away and is taken to see the Doomsday Chronometer, which Rosalio tells her was assembled in 15th century Prague before being split and is now complete save for the eighth piece.

Liv and Apolena go to the forest and see flattened trees, dead grass and a nun that Liv recognises as Professor Malone from Syra. River tells her that she is using a psychic wimple and that she has arranged to see Osm in the cells, leading Apolena to tell Osm's story of how he had seen a golden flash here which left behind molten metal that the Clocksmith and the Solvers cooled and took after having Osm imprisoned. River detects mineral traces from Syra with her screwdriver and suggests that Apolena return to the kitchens so that she and Liv can talk. She theorises that the Eleven's TARDIS materialised at that spot temporarily after Syra's destruction and deposited the metal, which the Clocksmith used to build the clock. They head to the prison to speak to Osm.

Cromwell arrives at a friary which he has taken as his home and has the Doctor taken to the tower by his guards. The Doctor tells him that the world is in danger.

Liv, River and Apolena enter Osm's cell and find that he has escaped through a tunnel from which Solvers are climbing, demanding the piece from them. Liv and Apolena escape whilst River uses her vortex manipulator to teleport away.

Cromwell tortures the Doctor on a rack, interrogating him about the Revelation Sect and ignoring his claims of friendship with King Henry when his dress sense was worse.

Liv and Apolena enter the Clocksmith's workshop where Liv uses a detection device which burns out, telling her that the piece is nearby. The Clocksmith arrives with his Solvers and has them seize Liv and Apolena before firing up the furnace and threatening to burn Apolena unless Liv gives him a ticket that he claims he saw her take.

Helen inspects the Doomsday Chronometer, which has an electric motor in place of the missing piece. She recognises a piece of it, which Rosalia tells her was found by Professor Salvatore at a lost property office at a train station in London. Before answering Helen's questions about the lost property office, Rosalia goes to answer the knocking at the door.

Liv realises that the Clocksmith is asking about the lost luggage ticket from 1998 and hands it over when he threatens to drop Apolena in the cauldron of lead. However, he uses a device to hold Apolena in stasis before killing her with it, telling Liv that nobody can leave there alive. He has the Solvers carry her towards the cauldron, planning on having her encased in molten lead.

Helen meets Professor Salvatore, who is actually the Clocksmith. He tells her that he has just left the Doctor.

The Doctor is freed from his chains by the Clocksmith, who then uses his device on him and tells him that he has read in the future that the suspected papist prisoner was killed after being found trying to escape. The Clocksmith calls for the guards, telling them that their prisoner is escaping, before heading to his TARDIS to meet a young lady that is waiting for him. The guards order the Doctor to stop.

Cast

 * The Doctor - Paul McGann
 * Liv Chenka - Nicola Walker
 * Helen Sinclair - Hattie Morahan
 * River Song - Alex Kingston
 * Thomas Cromwell - John Shrapnel
 * Apolena - Kasia Koleczek
 * Solvers / Abbot - Glen McCready
 * Rosalia - Emma D'Inverno
 * Octavian - Tim McMullan
 * The Clocksmith - Nicholas Woodeson

Continuity

 * The Doctor mentions that there are fixed points in history. (TV: The Fires of Pompeii, etc.)
 * The Doctor has coins from the planet Voga. (TV: Revenge of the Cybermen)
 * Helen and Rosalia talk about the National Museum and her art theft there. (AUDIO: The Red Lady)
 * The Doctor tells Cromwell that he met Henry VIII while wearing a colourful coat. (AUDIO: Recorded Time)