The Eighth Doctor is trapped by a rather sadistic man named Rawden, who delights in torturing him for information about the "brain worm". The problem is that Eight is successfully keeping up a Too Kinky to Torture façade, doesn't know anything about the brain worm to begin with, and has completely lost his memory (again). In exasperation, Rawden brings in C'rizz and threatens to torture him instead. Although the Doctor has absolutely no idea who C'rizz might be, he does know that letting others suffer is unacceptable. But since he still can't give any useful information, C'rizz is carted off to the torture expert, Mr. Twyst, to be broken.
In flashbacks, we see how team TARDIS arrived inside the Cube and met a group of psychic humans: Tessa, Jane and Latch. (The fourth one, Marcus, was found early on by Charley with his skull turned inside out.) They're soon enough haunted throughout the Cube by a monster called the brain worm, the TARDIS vworps off, everyone gets separated, and it's revealed that the humans are all discarded Psycho Prototype soldiers. They were locked up after the Great Offscreen War when Rawden realised their psychic powers couldn't be turned off again. While Charley befriended the soldiers, C'rizz revealed that he could shield himself and Charley from having their minds read by the soldiers... because he's moderately telepathic. And although Charley still has no idea of most of C'rizz' peculiarities, let alone his definition of "saving" people, it's revealed (to us, not to Charley) that C'rizz picked up this particular skill from someone he killed.
The Doctor is forced by Rawden to be hooked up to the same machine that gave the soldiers their powers. After all, if it enhances brain waves, it might improve his memory. Seeing C'rizz being severely tortured, the Doctor relents, spends a few long moments in agony, and... is able to Reverse the Polarity of the machine through sheer instinct and overload his own mind with temporary psychic ability. He telekinetically freezes Rawden and Twyst in place, drags a dying C'rizz along and heads for the exit. He heads right back in when he realises that the mysterious brain worm has been eating his memories and there's a way for him to get them back.
The brain worm turns out to be a sentient mass of raw psychic energy, residing in the mind of Tessa, who was the very first prototype. The Doctor convinces Tessa to team up with him in order to save C'rizz' life: her psychic healing ability and his instinctive knowledge of alien races might heal C'rizz' massive internal injuries. In the process, the Doctor surreptitiously steals the brain worm from Tessa, claims back all his memories and traps the thing inside his mind. His personality still hasn't slotted into place quite right, but he's able to remember that Charley is his best friend. When Twyst (arriving on the scene) tries to shoot Charley, though, the Doctor's raw desire to murder the man on the spot allows the brain worm to leap out, kill Twyst and start a bit of Body Surf. It really, really wants to escape from the cube. Latch, the strongest psychic (and the most adept killer) of the bunch, makes a Heroic Sacrifice to stay inside the Cube with the worm stuck into his mind until they both die.
Tropes:
- AcCENT upon the Wrong SylLABle: The Brain Worm once it got someone's mind.
- Amnesiac Hero: Eight's lost his memory. Again.
- Asshole Victim: Mr. Twyst.
- The Assimilator: C'rizz reveals that he absorbs people's powers when he "saves" them. He's moderately telepathic as a result.
- As You Know: Charley can't stop being a Deadpan Snarker when the Doctor is summarizing the story, despite him needing it because it took his memories.
- Badass Boast:The host to the Brain Worm: It's — it's — I'm going to kill you.
The Doctor: C'mon then... If you think you're hard enough. - Big Damn Heroes: The Doctor, and C'rizz, but the he's just following the Doctor.
- Can't Argue with Elves: The Doctor, once he regains a bit of his memory, is on a roll in this adventure.
- Cold-Blooded Torture
- Death Equals Redemption: Latch takes the Brain Worm with him back into the Cube.
-
Development Hell: The episode was written quite a long time before being recorded, and had to undergo extensive re-writes since it was originally meant to take place in the Divergent universe. - Heroic Sacrifice: Gordon Latch takes the Brain Worm with him, into death.
- Just Between You and Me: Inverted Trope and Subverted Trope by the Doctor. As he's being tortured he escapes and puts his torture on his captors, so they ask him what he's going to do so he says: "What, now that I have you at my mercy I'll tell you all you need to know?"
- Loss of Identity: Eight without his memories is a bit of a dick. This does allow him to save Charley's life, since his desire to murder Twyst causes the brain worm to leap out and kill the man.
- Meaningful Name: Rawden is "warden" a bit shuffled.
- A Mind Is a Terrible Thing to Read: Tessa peers into C'rizz mind when she heals him. She doesn't want to talk about it.
- The End... Or Is It?:At the end the story, the Brain Worm's indicated to still be alive. Outside the Cube.
- Phlebotinum Analogy:The Doctor: "The Brain Worm is safe inside my mind. Like the Tower of London."Charley: "People have broken OUT of the Tower, though."
- Playing with Syringes: Twyst.
- Power Limiter: The Cube is this for Psychic Powers.
- Psychic Block Defense: The Doctor has a lot apparently.
- Psychic Powers: All kinds.
- Psycho Prototype
- Punctuated! For! Emphasis!: The Brain Worm once it gains Latch's voice speaks in this manner.
- The Reveal: Of the actual Brain worm.
- Reverse the Polarity
- Running Gag: Eight. Amnesia.
- The Doctor does a Reverse Polarity on a Psychic Inhibitor.
- The Tower of London being a Cardboard Prison.
- Shout-Out: the Cube is a prison?
- The whole issue with the Brain Worm seems similar to The Thing (1982).
- Torture Porn: Oh yes. Both the Doctor and C'rizz spend much of the episode being severely tortured. Eight tries to put on a Too Kinky to Torture façade, but can't keep it up throughout the more unpleasant moments.
- Two Beings, One Body: The Brain worm is this to its host.
- Whole-Plot Reference: To Cube.
- You Cannot Grasp the True Form: Of the brain worm.
- Xtreme Kool Letterz: "Twyst"
YOU ARE ABOUT TO ENTER THE CUBE
ALL FORMS OF TELEPATHY ARE PROHIBITED.
DO NOT ATTEMPT TELEPORTATION UNDER ANY CIRCUMSTANCES
PSYCHIC POWERS WILL BE FORCIBLY REMOVED
(MENTAL SURGERY IS COMPULSORY)
CAUTION
YOU HAVE NO RIGHTS
YOU HAVE NO POWERS
YOU HAVE NO DEFENCE
YOU ARE NOW INSIDE THE CUBE
