Alit in Underland was the sixth and final short story published in The Missy Chronicles.
One night on Floor 0507 of the Mondasian colony ship, sometime after Nardole's shuttlecraft from Floor 1056 crashed on the solar farm, Alit sneaks out of the farmhouse to follow the Saxon Master and Missy, who, despite Nardole and Hazran's protests, are travelling to Floor 0508 to stop the patients and find a way to escape the colony ship. Alit follows the duo to the crashed shuttle and hides behind it while the Master and Missy use the shuttle's rope ladder to climb down into the walkways between Floor 0507 and Floor 0508. Alit decides to return to the farmhouse, only to run straight into one of the patients. She escapes down the ladder and is confronted by the Master and Missy, who decide to let her join them on their journey.
In the walkways, the Master speculates that a service lift is nearby that will take the group to Floor 0508. Alit thinks the patient she ran from earlier - who Missy has begun to call "Topknot" - is still following them, and the group speeds up after hearing it. Eventually, Missy detects a nearby service-cradle, and the Master quickly burns through its seals with his laser screwdriver. Suddenly, Topknot emerges from the darkness and tries to grab Missy, who defends against it with her sonic umbrella, while the Master rips off Topknot's chest cloth and burns a small incision into the patient's chest with his laser screwdriver; it stops, allowing the Master to alter its voice box settings so that Topknot recognises his vocal commands. The Master then changes the patient's root command so that it no longer recognises beings with two hearts as human, allowing him and Missy to use Topknot however they wish. Alit climbs through a small gap in the hatch‘s bars and unlocks the door. The Master and Missy enter as well, and Topknot operates a control, causing the service-cradle to descend into Floor 0508. Missy questions the Master about his real plan, knowing that he isn’t really going to stop the Cybermen or find an escape; the Master states that he intends to alter the Cybermen’s definition of humanity so they no longer recognise beings with two hearts as human, allowing him to regain control over them and use them to conquer the galaxy.
As dawn breaks, the service-cradle lands by a huge rail network. The group spend the majority of the day following and riding on various pieces of automated farming equipment, before stopping at a network of buildings. The Master then orders Topknot to scan for technology that can be used to access the ship’s systems so that he can hack into the patients on Floor 1056. Topknot points to a tower at the centre of the buildings, and the group discover it to be a huge network of storage bays, silos and warehouses.
As dusk falls, the group explore a large storage area for farming tools, before hearing voices nearby. They briefly hide before the Master notes that whoever are nearby are looking for life-forms with two hearts, realising they are looking for him and Missy. He then begins walking towards the voices, Missy and Alit following. They find the source of the voices to be a group of six Cybermen, whose Cyber-Leader explains that the Cyber-Planner has assigned them to capture the two Masters for interrogation concerning the change to the Cybermen's programmed definition of humanity. The Cybermen draw their cyber-guns and the Leader orders the group to follow them to the lifts back to Floor 1056. At the lifts, the Master realises that the Cyber-Leader has secondary orders, and as two Cybermen move to trap them, Missy stuns the entire patrol with her sonic umbrella while the Master uses his laser screwdriver to destroy the Cyber-Lieutenant. Alit and Missy hide in a closet down a side corridor, and witness the Cyber-Leader render the Master unconscious before throwing him into a nearby storage cell. The Leader then orders one pair of Cybermen to locate Missy and Alit, and the other to activate the Cybermats before returning to Floor 1056. Missy and Alit escape by opening a far wall and venturing down another corridor.
Missy and Alit lead the Cybermen on an erratic path to the central control tower, stopping by a nearby grain store on the way; Missy stuns a group of mice and contains them in small fence wire cages that the pair wear around their necks, two for Alit, one for Missy. The latter explains that the grouping of multiple life signs so close together will briefly trick the Cybermen’s scanners into registering the pair as life forms with three hearts, and as they are searching for life forms with one or two hearts, they will ignore Alit and Missy for a short while. Eventually the duo find Topknot, and Missy orders the Cyberman to locate the control tower and to keep watch for the Cyber-patrol. The pair take a lift to the top of the tower to the hub of a weather system across the entire floor.
Missy explains to Alit that the Cybermen intend to use the Cybermats to weaken the humans on Floor 0507 so that the solar farm can be conquered more easily. Upon hacking into the ship’s systems via the room’s service hatches, Missy discovers that all the cyber-technology the Master set up on Floor 1056 has a failsafe system; in the case of the patients, the system forces them to remain in the hospital if turned on. After discovering this system in the Cybermats, Missy activates it, forcing the Cybermats back to Floor 1056 and preventing their attack. Missy then has another idea, and instructs Alit to fetch some boots they passed earlier while she informs Topknot of their plan to rescue the Master.
At the lifts, Missy rescues the Master from his cell and explains that she used Topknot to distract the Cybermen, when Alit arrives wearing some black rubber boots and carrying identical pairs in each hand. The two Masters put on their boots and the trio run for the nearest exit. Missy notes that they have located the lifts, and can use such knowledge to find them on Floor 0507 and reach the Doctor’s TARDIS. Suddenly, the Cyberman patrol reappears and begin firing at the trio. The Master, after being informed by Missy, pulls out his laser screwdriver and fires at the metal deck, creating an electrical discharge which causes the Cybermen to fall to the ground, dead. Alit, in shock, realises that hers, the Master’s and Missy’s rubber boots protected them from the discharge.
The trio manage to locate a conveyor belt system feeding straw bales to the higher floors, and use it to quickly return to Floor 0507. As they ride up and away from Floor 0508, Alit asks Missy why she didn’t stop the Cybermen with the failsafe system if she managed to stop the Cybermats, but Missy simply dismisses the idea as a long shot, before telling Alit to keep it a secret between them. At Floor 0507, the group arrive inside a large stable, home to several horses and carts. They harness a cart to one of the horses and begin riding back to the farmhouse. Alit notices a sinister look in Missy’s eye, as the latter speculates that killing her previous incarnation is the only way things can end...
- The Master, Missy, and Alit wear Wellington boots.
- The story is set during TV: The Doctor Falls, during the two weeks after the Twelfth Doctor, Bill, Nardole, Missy and the Saxon Master arrived on Floor 0507. Thus, this is the last story, chronologically, to feature Missy before the episode depicting her death, forming a bookend with PROSE: Dismemberment, which opened The Missy Chronicles as her earliest story.
- The Doctor is still recovering from being electrocuted by a Mondasian Cyberman. (TV: The Doctor Falls)
- Alit thinks the Cybermen are scarecrows. (TV: The Doctor Falls)
- The Master tells Missy her sonic umbrella and hat are reminiscent of Mary Poppins and she tells him they've always enjoyed children's viewing. The Master then reminisces about the sun from the Teletubbies and how he thought it would look the same on the Mondasian colony ship. (TV: The Sound of Drums) He then compares Teletubbies to Clangers. (TV: The Sea Devils)
- Missy says she recently watched Frozen with the Doctor. (TV: Empress of Mars)
- Missy calls the Master out on not wanting to regenerate into a woman and the Master says women always stab people in the back. In their near future, Missy will literally stab the Master in the back and he, in turn, will shoot her in the back. (TV: The Doctor Falls)
- Missy recalls several women that she's used and abused throughout her lives: Galleia, (TV: The Time Monster) Kassia, (TV: The Keeper of Traken) Chantho, (TV: Utopia) Miss Trefusis, (TV: Last of the Time Lords, The End of Time), and Lucy Saxon. (TV: The Sound of Drums, Last of the Time Lords) The Master mocks Missy for remembering their names and Missy says she's been making herself remember names lately. (TV: The Lie of the Land)
- The Cybermen ordered to capture the Master and Missy are CyberNeomorphs and possess identical Cyber-guns. (TV: Earthshock, The Five Doctors)
- A Cyber-Planner leads the Cybermen on Floor 1056. (TV: The Wheel in Space, The Doctor Falls)
- Missy explains that the Cybermen use Cybermats to spread disease on human colonies. (TV: Revenge of the Cybermen)
- Missy reminds the Master that they always "dress for the occasion". (TV: Doctor Who)
- Missy decides to kill the Master. (TV: The Doctor Falls)
- Missy has already planned for the death of her former incarnation once, using Lucy Saxon to shoot him and then to concoct the mixture that prevents his full bodily return. (PROSE: The Unwanted Gift of Prophesy, TV: Last of the Time Lords, The End of Time)