P is for... Pting

Diminutive creatures noted for their insatiable appetite for anything inorganic - especially if it provided them with an energy source. They were reputedly indestructible and could survive in the vacuum of space. One of them once wiped out an entire space fleet. They could be rendered immobile for short periods by staser fire, however, but made for extremely difficult targets.

The Doctor and her companions encountered one when it infiltrated a hospital ship, the Tsuranga, carrying them and a number of patients and staff. The creature began eating its way through the ship's infrastructure, aiming for the anti-matter power core. 

An attempt to lure it into an escape pod failed, so the Doctor was forced to devise an alternative scheme. A detonation device was rigged to attract it and it consumed this instead, before being ejected from the vessel through an airlock.

On exploding, the Pting merely absorbed the resulting energy and survived to float away through space.

The Doctor later encountered another member of the species, which she nicknamed "Tiny", on a penal asteroid run by the Judoon.

Appearances: The Tsuranga Conundrum (2018), The Timeless Children (2020), Revolution of the Daleks (2021)

• Though the episode was written by Chris Chibnall, the Pting was actually the creation of writer Tim Price. He had been a member of the writers room for Series 11 but had been unsuccessful in getting a story commissioned. Chibnall liked the alien he had devised, however, and Price agreed he could use it.

P is for... Psi

Psi was one of the people recruited by the Doctor to help rob the Bank of Karabraxos - notorious for its high levels of security. None of the thieves knew that the Doctor was behind this heist - even him, as they had all willingly handled a Memory Worm which wiped their recent memories. This was so that they couldn't reveal anything if captured. The bank employed a creature known as the Teller which could psychically sense guilt.

Each of the gang was promised a reward - something which the bank held in its vaults. Psi had undergone a technological upgrade which allowed him to interface directly with any computerised systems. In doing so, his longer term memories had been removed and stored on a chip, and getting this would be his reward. 

They were also given a suicide device - a ripper - to use in the event that the Teller caught them and destroyed their brains seeking their guilt. After helping to breach the security systems, Psi sacrificed himself by downloading data about various notorious criminals into his mind, which drew the Teller away from the Doctor and Clara. This then allowed them to reach their goal - actually the rescue of the Teller's mate.

It later transpired that the ripper was really a teleport, which took them to the safety of the TARDIS. Psi gained his memory chip, which allowed him to recall his family.

Played by: Jonathan Bailey. Appearances: Time Heist (2014).

• Pretty much everywhere these days, he started off as a child actor with the RSC and also played Gavroche in Les Miserables in the West End. His first significant TV role was as the corruptible local journalist in Chris Chibnall's Broadchurch.
• Period drama Bridgerton really put him on the map, before he moved to the big screen with Wicked and its sequel, and the male lead role in Jurassic World Rebirth.
• He hasn't given up the theatre. I saw him in the title role of Richard II at the Bridge Theatre in London in 2025.
• In 2024 he set up an LGBTQ+ charity - The Shameless Fund.
• Voted sexiest man alive in 2025.

P is for... Programmers

Two of the staff who helped to operate the Game Station - the space station in orbit above Earth formerly known as Satellite Five. They were employees of the Bad Wolf Corporation, responsible for ensuring that the station continually broadcast hundreds of game shows to the inhabitants of the planet below.

Programmer Davitch Pavale noticed irregular activity in one of the Big Brother games, and alerted his female colleague who had noted similar activity in a Weakest Link she was monitoring. This involved a pair of new contestants who were not taking the deadly games seriously. The Doctor and Rose had been abducted and transported into the games - the Doctor into the Big Brother house and Rose into a Weakest Link contest. The situation worsened when the Doctor broke out of his game, taking another contestant, Lynda, with him. When they alerted the Controller, through whom all output from the Game Station was broadcast, she instructed them to take no hostile action.

The Doctor, Lynda and Captain Jack Harkness - who had ended up on What Not To Wear - were captured by security guards but soon escaped and began making their way towards the control room.

Despite the fact that they appeared to be armed, the Controller once again refused to take action against them. 

This was because she was under the control of the Daleks, who had been responsible for bringing the Doctor and his companions here.

The Doctor warned them of an imminent Dalek attack, and the Programmers joined Jack in helping to defend the Station. Both were killed when their weapons proved ineffective against the invaders.

Davitch had carried a torch for his colleague, only letting her know of this before they perished.

Played by: Jo Stone-Fewings (Davitch Pavale), Nisha Nyar. Appearances: Bad Wolf / The Parting of the Ways (2005).

• It would probably be cause for controversy these days but the Female Programmer doesn't merit a name.
• Nisha Nyar has featured on many Big Finish audios.
• She previously played (uncredited) a Kang in Paradise Towers. 
• Jo Stone-Fewings is primarily a theatre actor, having appeared in over a dozen Shakespeare productions, many with the RSC.
• He had previously worked on a Russell T Davies drama - Mine All Mine - in 2003.

P is for... Pritchard

Richard Pritchard was a representative of Vector Petroleum, who controlled a mining complex known as The Drum in the Highlands of Scotland. He was Vice President of Subaquatic Resources, for The Drum was located deep beneath a man-made lake in a flooded valley.

As senior company staff member on the team, he took charge when commander Moran was killed in a freak accident. A capsule of unknown origins had been found on the floor of the lake and brought on board. Its engines fired unexpectedly and Moran was killed. Pritchard was interested mainly in how this apparently alien technology could be exploited by the company. He was especially interested in a missing power cell, which the Doctor had drawn the crew's attention to. 

Despite the appearance of ghostly figures which had begun to haunt the complex - including spectres of Moran and a figure dressed like a funeral director - Pritchard decided to don diving gear and go outside alone to find the power cell. Moran's ghost turned up and killed him, trapping and drowning him in the airlock before he could suit up.

Pritchard then joined the ranks of the ghosts. All were lured into a Faraday Cage where they were trapped by the Doctor, and this was then fired into space where the ghosts - really psychic transmitters - would dissipate over time.

Played by: Steven Robertson. Appearances: Under The Lake / Before The Flood (2015)

• Robertson is best known for his regular role in crime drama Shetland. He was born and raised on the Shetland Islands. 
• He also appeared in supernatural drama Being Human. This was in its fifth series, when he played civil servant Dominic Rook whose government department dealt with supernatural phenomena.