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Thinking Warrior was the third short story in the Short Trips anthology Short Trips: 2040. It was written by Huw Wilkins. It featured the Eighth Doctor.


Perseus Dynamics has suffered a hacker attack. Julia Carthy, David Gordon and Simon Ordell are meeting to discuss the situation. All information, including that of the Peacekeeper project, has been wiped. Gordon, from Perseus security, is currently having the staff checked out, knowing that most hacker attacks come from within. An investigator from CMO, the company that commissioned the Peacekeeper project, is arriving soon, and Ordell is assigned to be his guide.

Ordell meets the investigator, who introduces himself as the Doctor, and takes him on a brief tour. They then head for the work area, where one of the scientists, Marti Elser, reassures Ordell that, although all info was wiped, he will be able to retrieve it from the backups, though it will take several long days. The Doctor is introduced to Pollux, the sentient beta version intelligence core of Peacekeeper. The alpha version, Castor, was erased in the attack. Pollux describes the attack and how he avoided being wiped.

Gordon and Carthy meet Phillip Green, another Perseus security man, for lunch. Green tells them about the Doctor's involvement with some Unit group. Gordon and Green inform Carthy about their plans to place blame on rogue hackers in China for the attack, diverting suspicion from their own actions. When Ordell and the Doctor arrive for lunch, Gordon informs the Doctor that the attack seems to have come from China.

Later, taking a break from reading computer files, the Doctor has a chat with Pollux. Pollux accuses the Doctor of being part of the aliens backing the Perseus Corporation — he detected the Doctor's binary vascular system. The Doctor denies involvement with Perseus, and then asks Pollux why he hacked into the company. Pollux decides to trust the Doctor. He explains that Castor had been constantly upgraded, and each time he "dies a little more". Castor asked him to "kill" him. The Doctor learns that Perseus is using the Peacekeeper project for more than what was assigned — they are trying to create artificial soldiers. He wonders why Ordell, a Royal Marines major, would be involved, but Pollux explains that Ordell was involved in a friendly fire incident and that Perseus is holding that information over his head.

The Doctor confronts Ordell. Ordell explains that the friendly fire incident was not his fault, but that Perseus faked the evidence to place the blame on him. The Doctor convinces him to help expose Perseus' plans, and Ordell agrees.

The Peacekeeper project is completed, and Ordell returns to active duty.