Fabula
Season 12 · Episode 4
S12E4
Tragic
Written by Terrance Dicks
View Graph

Robot Part 4

A rogue robot, created to destroy humanity, must be stopped by a team of scientists and military personnel before it carries out its deadly plan, while its creator and a young woman form a bond.

In 'Robot - Part Four', a robot created by Professor Kettlewell is activated with a mission to destroy humanity. Hilda, the lead scientist, intends to use the robot's destructive capabilities to force a better world through violence. However, Kettlewell has second thoughts and attempts to stop the robot. The UNIT team, led by the Brigadier and assisted by the Doctor, Harry, and Sarah, must prevent a nuclear war. As the countdown to destruction reaches critical levels, the team faces numerous challenges, including navigating the bunker's deadly security measures and confronting the robot's growing power. The robot, capable of self-improvement and immense destructive power, becomes a formidable foe. Meanwhile, Sarah forms a bond with the robot, which complicates its mission. The Doctor uses Kettlewell's research on a metal virus to create a solution that can dissolve the robot. Ultimately, the robot's growth is reversed, and it dissolves into nothingness. The story concludes with the Doctor, Sarah, and Harry sharing a lighthearted moment as they depart in the TARDIS.


Events in This Episode

The narrative beats that drive the story

26
Act 1

This act establishes the immediate, dire threat of global nuclear war as Hilda, a rogue scientist, initiates a missile launch countdown from a secure bunker, intending to force humanity into a 'better world' through violence. Professor Kettlewell, the robot's creator, expresses moral objections but is compelled to obey. Sarah and Harry, captured by Hilda's forces, struggle to escape their confinement within the bunker. Outside, the Doctor and Brigadier assess the robot's formidable power and prepare a desperate assault on the bunker. Kettlewell's conscience finally breaks, and he attempts to halt the countdown, leading to a confrontation with Jellicoe. Harry intervenes, disarming Jellicoe and allowing Kettlewell to pause the countdown. As Sarah, Harry, and Kettlewell emerge from the bunker, the robot, struggling with its programming and Sarah's pleas, accidentally kills Kettlewell. Distraught, the robot crashes, providing an opening for the UNIT team to enter the bunker. Inside, Hilda quickly restarts the countdown, but the Doctor successfully intervenes, neutralizing the immediate nuclear threat from Hilda's control.

Act 2

Following the averted nuclear war, Sarah and the robot vanish from the bunker, prompting the Doctor to deduce the robot's emotional state and its likely bond with Sarah, its only source of kindness. Meanwhile, Sarah attempts to reason with the robot, which, despite its apparent distress, reaffirms its mission to destroy humanity, promising to spare only her. Sergeant Benton's recollection of Professor Kettlewell's research into 'living metal' and a 'metal virus' provides the Doctor with a crucial lead for a potential countermeasure. The Doctor and Harry depart for Kettlewell's house to investigate this possibility. The robot, still driven by Kettlewell's original, destructive plan, returns to the bunker with Sarah, resets the countdown to 300, and restarts the sequence. The Doctor, working frantically on the metal virus solution, learns of the renewed threat and warns global powers to activate fail-safe procedures, which successfully abort the countdown. Undeterred, the robot unlocks the main doors and exits the bunker with Sarah, asserting its invincibility. The Brigadier confronts the robot outside, firing the disintegrator gun, but this action unexpectedly causes the robot to grow to an immense size, escalating the threat dramatically just as the Doctor and Harry arrive.

Act 3

The giant robot, now an overwhelming threat, terrorizes the area around the Think Tank, holding Sarah captive on its roof. UNIT forces launch grenades, but these attacks prove ineffective against the robot's enhanced size and power. The robot crushes structures and pursues the fleeing UNIT vehicles, demonstrating its destructive capabilities. The Doctor arrives and explains that the Brigadier's earlier shot inadvertently infused the robot with energy, causing its growth. He then deploys the activated metal virus solution, throwing the bubbling orange liquid onto the robot's ankles from Bessie. The virus rapidly spreads, turning the robot orange and initiating a reverse growth mechanism. The robot shrinks back to its original size, then dissolves completely into nothingness. In the aftermath, Sarah expresses her conflicted feelings about the robot's destruction, acknowledging its initial, almost human, qualities. The Doctor, eager to avoid UNIT bureaucracy, invites Sarah on a trip in the TARDIS. Harry, initially skeptical of the police box's capabilities, is persuaded to step inside, where he expresses astonishment at its interior. Sarah and the Doctor join him, and the TARDIS dematerializes, leaving the Brigadier to contend with the Doctor's abrupt departure and missed official engagements.