The Turn of the Screw (audio story)

The Turn of the Screw was the third story of the eighth season of Big Finish Productions' Short Trips series. It was performed by Yee Jee Tso, who played Charlie Sato, and also featured the Eighth Doctor and Ruth Matheson.

Publisher's summary
Charlie Sato has been chasing a bit of alien junk from England to Puerto Rico. He's finally got his hands on it - but now he's got to get it safely off the island. The aliens he stole it from want it back, and someone else has hired a group of thugs to get hold of it. And then there's the original owner - he might come looking too.

All this for a screwdriver? Someone, somewhere must want to unscrew some pretty important screws.

Plot
After tracing it from Leadworth to San Juan, Charlie Sato has stolen the Doctor's broken sonic screwdriver, although he is unaware of what it is, and is under orders to take it to the Vault. He waits to be smuggled to Miami on a cargo ship and overhears those he stole the device from telling a police officer about how he had stolen something from them. He hides the screwdriver and his gun, puts on an orange tabard he had stolen and, after claiming to speak only Cantonese and being frisked by the police officer, departs.

Sato is knocked unconscious and wakes up tied to a chair in a garage, surrounded by two men and a woman. They know his name and that he works for UNIT and beat him up when he claims he no longer has the screwdriver. After a while, they bring in the Doctor, whom they believe to be a specialist. He gives Sato a drug which heals his wounds and removes his pain before taking a payment from the woman and discreetly releasing him from his bonds. The Doctor holds one of the men at gunpoint and Sato takes another of their guns. They leave in a Volkswagen Beetle.

The Doctor introduces himself to Sato, who is initially sceptical, and tells him that he picked up his call to UNIT whilst on the trail of the thugs. They return to the docks to recover the screwdriver, but it has disappeared and the Doctor believes that it has been taken by the thugs, who are actually alien parasites called the Naptra. They head to the Naptra's hotel, where Sato had stolen the screwdriver from them, and the Doctor works out where they have gone from their calculations; they plan on sending a sonic signal from a nearby radio telescope to undo an artificial fold in spacetime located between the orbits of Jupiter and Saturn and release a prisoner of the Drud.

Sato and the Doctor are shot at and take cover. They enter the building and find the Naptra holding the telescope staff at gunpoint whilst operating the telescope with the screwdriver wired to it. The Naptra explain that they arrived here against their will and that they will die if they do not return to their host, but the Doctor promises to synthesise what they need if they stop their plan. They agree and hand the screwdriver over to the Doctor.

During the car journey back to San Juan, the Doctor examines the screwdriver and finds that it is not one that he has created yet. As there is a programme still running on it, the Doctor declines to give it to Sato and instead plans on putting it in a drawer aboard the TARDIS. Upon arriving, the Doctor gives Sato the money he was given by the three goons to pay for his return home and leaves with the Naptra. Sato encounters the trio at the docks and convinces them that the screwdriver has gone; they believe him, but beat him up. Later, he is picked up by UNIT and tells Captain Matheson his story and she promises to deal with the goons, having found out whom they were working for.

Characters

 * Charlie Sato
 * Eighth Doctor
 * Ruth Matheson

Worldbuilding

 * Sato speaks Cantonese.
 * Sato claims to have come to San Juan from Shanghai.
 * Roxanna would beat up Sato's sister when she was in fourth grade. She lives in Richmond.
 * Sato has been trained to resist truth drugs.
 * The Doctor's car has a cassette deck. When he and Sato drive off, it plays A Hard Day's Night by the Beatles.
 * The Doctor uses his psychic paper.
 * The Naptra are parasites from another dimension. They have white faces and used makeup to appear human. They usually live on the Drud like fleas.

Continuity

 * The Doctor drives his Volkswagen Beetle. (PROSE: Vampire Science)
 * The damaged sonic screwdriver is first found in Leadworth, where a future incarnation of the Doctor lost it. (TV: The Eleventh Hour)
 * There is a programme running on the damaged screwdriver, (TV: The Day of the Doctor) but the Eighth Doctor is not sure what it is for and does not plan to abort it.