Ascension of the Sandmen
Over a scene of deep space filled with debris, the voice of Kracus narrates that the Sandmen have been defeated after winning a billion battles. After bringing terror to the universe, their empire has finally fallen. As a lone Sandman hand floats closer, he adds how "that which is dead can live again... in the hands of a believer."
In deep space of the far future, Georgia and David Tennant go to a refugee planet, having followed the coordinates they previously got from Roald Dahl. However, they have landed half a mile out, forcing them to carry equipment to the last remaining human settlement. Georgia theorises that the majority of the species has been wiped out by the Sandmen, but the enemies are weak too. The group goes to find the final eight surviving humans.
In the settlement, a middle-aged man called Zlax discusses repairs of their Gravraft with a woman called Garald. She explains they will take at least another day, but two Sandman spaceships arrive overhead, startling a teenage boy called Nathaniel. Georgia offers her help and the group set up their equipment. As Zlax explains that they have only run from the Sandmen before and their escape ship is botched, Georgia tells him to get the others inside and not run.
As the humans set up the tech, David is met by a man called Markon and his mute younger brother Fletch to set up a forcefield. With the other humans (including a young woman called Mascot, a young man called Ryan, and another older woman) never having been fighters, the gizmos are powered up. However, a swarm of flying Sandman Drones appears, destroys the equipment with precision, and kills Fletch and the older woman as they try to run.
As the drones leave, Georgia commands the others to get to their ship and leave, and David to go with them, while she holds them off. Suddenly, Kracus appears to Georgia. Although shocked by her, he has backup from two Sandman guards. Georgia decides to act as bait to help the others escape. As the humans and David run, Ryan is cut off from them, but the rest run to the Gravraft. They are forced inside for takeoff, even though they are missing Georgia, Ryan, Zlax, and Nathaniel. Markon assumes they are all dead and they take off.
Meanwhile, Georgia takes cover and stumbles upon Ryan and the others. As she prepares a grenade, Kracus arrives and tells them to surrender. Nathaniel is confronted by Kracus, saying he is the only remaining human, but Kracus knows he is lying and kills Zlax. He wonders whether to let Nathaniel live so he can warn any others of the Sandmen's power, but Georgia creates a diversion and they run. Without the Gravraft, they go to steal Kracus's Sandman ship instead. Inside the ship, Georgia works on hot-wiring it, already being a pro. However, Nathaniel identifies a faster way and the ship starts up. Taking off, Kracus looks up, furious.
The remaining refugees with David fly through space. Although Garald and Markon argue about how to run the ship, Mascot explains they are heading toward the planet Xe Hamo and a phenomenon called "the Boundary" which teleports anyone who finds it to random locations in the universe. However, by pushing the ship too hard, its ailing engine explodes.
On the Sandman ship, Nathaniel also sets a course for Xe Hamo, planning on getting there first. Nathaniel explains one fo the first things he was ever taught in life was how to hijack and destroy Sandman ships. Ryan reveals that he got separated from the other humans because he has dyspraxia. He also says that he dosen't like weapons.
As they talk, a hologram of Kracus appears and he and Georgia talk. He explains that the Morpherium does know of her, but he will stop her and destroy humanity. She points out his internal conflict of hating who he used to be and not being a perfect Sandman, but he agrees and points out he is ready to carry the death of everything inside him. As he leaves, Georgia is left shaken.
Inside the Gravraft, everyone survives, but they are still floating in space and running on emergency power. Looking out of a viewpoint, David realises they are floating aimlessly through a Sandman battle site, complete with dormant ships. Markon notices a docking bay on one of them, and the two give the refugees a plan to channel their remaining life support energy to accelerate onto the ship. With nothing to lose, they try it and barely make it onto the ship alive. The ship is enormous inside, with their arrival making its systems start working again. However, as they look around, another Sandman ship arrives nearby, carrying Kracus and his guards, ready to hunt the humans down.
Georgia's Sandman ship reaches what they think is the planet of Xe Hamo, with Georgia broadcasting to the run-down, temporary settlement if anyone is there to answer them. However, Xe Hamo turns out to be one lone elderly man, who does not believe any more humans exist. Georgia parks up, happy to see a friendly face.
Meanwhile, David, Garald, Markon, and Mascot explore the ship. Markon explains they must be nearing Morp Control, making the others realise they have landed on a Sandman war carrier. Finding the control deck, the refugees plan to reach Xe Hamo with it, cross the Boundary, and settle in the carrier until they find a habitable planet. David and Garald decide to explore the ship.
Reaching level 107, the ship starts moving and Garald finally begins to feel some optimism. Having a look inside another enormous room, Garald starts to warm to David. They come to a series of vertical pods and David kicks one open, only to be met by a dormant Sandman of a new and battle-ready design. David belatedly realises there must be around a thousand of these Sandmen in this room alone, ten rooms on each floor, and several hundred floors to the ship, numbering the Sandmen in their millions. Meanwhile, in the docking bay, Kracus and his Sandman guards arrive, driven by the Morpherium.
Georgia, Ryan, and Nathaniel finally meet Xe Hamo who is stunned to see living humans. He explains how he and a handful of others fled the Sandman camps and was sent for conversion, but he barely escaped to this planet. As the word spread, many others arrived, but he has since helped them all through the Boundary and waited behind for other survivors ever since.
Meanwhile, at MorpControl, Markon, and Mascot hear a siren sound to alert them that they have been boarded, and they contact David and Garald to get them back immediately. The duo barely escapes Kracus and reaches the others, as Kracus looks in awe at the Sandmen ready for him. Garald warns the others that they must not bring Sandmen to the Boundary, but they have no other choice. In the carrier, Kracus awakens one of the advanced Sandmen, a Morpheus Warrior, and attacks it with his guards, causing it to scream, deeply unnerving the humans.
Elsewhere, Xe Hamo shows the Boundary to Georgia, Ryan, and Nathaniel, which appears as a rippling purple sheet of energy. Georgia has no idea how it works but is willing to risk it.
Garald flies the Sandman ship towards Xe Hamo's planet as the Morpheus Warriors wake up and salute Kracus, ready for their ascension. He calls the group to say he knows they are there and David is able to contact Georgia, explaining the situation. As the Sandmen reach their last door, Georgia urges her friends to evacuate, but they are trapped. Then, the Boundary unexpectedly clears, and Xe Hamo is stunned as Georgia sees the destroyed capital city of Gallifrey on the other side.
Suddenly, Alverta Hyde leaps through the Boundary, impressed with his entrance, and tells Georgia to be afraid, as "everything is about to change. Forever."
The Metastopholes Children
Alverta forces Georgia to join him on Gallifrey through the Boundary or else he will use his Atom Reformer on Ryan, Nathaniel, and Xe Hamo. Pulling her through, the others intend to follow, but a Sandman Carrier appears overhead.
Inside, David, Garald, Markon, and Mascot attempt to sprint from Kracus and his Sandmen. Mascot holds them off as the others scramble through a vent, but she is killed in the process.
Georgia and Alverta land outside the ruins of Gallifrey's Capitol and he taunts her for his work. He plans on showing her a tour of the ruined Citadel and reminds her there is nothing she can do to help her friends or her husband.
On the Sandman Carrier, the group makes it to a storage vault as David comes up with a mad idea. Reaching another carrier full of disabled Morpheus Warriors, he plans to hide in their mocous membrane as a disguise. Knowing how nasty the insides of mucous membrane may be, Garald works to disconnect the suits from their shared neural network as the others work on the bodies inside. Meanwhile, Xe Hamo shows Ryan and Nathaniel his very limited weapon store. Although Ryan has an aversion to weapons, the others say he has no choice.
Alverta leads Georgia to the centre of the Citadel. As he talks, a mini scanner in his pocket notifies him that the Sandmen have reached the Boundary. He extends a holographic call to Kracus and they introduce themselves. Alverta coaxes him to join him on Gallifrey and successfully convinces them to send some Sandmen to Xe Hamo's planet as the carrier sets course for Gallifrey. As dozens of Sandmen land in front of the humans, they prepare for battle. Using sentry guns and a large bomb, they manage to take out many of the Sandmen, but are forced to flee as more arrive to take their place.
Meanwhile, David, Garald and Markon work on the moucous membrane, and get ready to cover themselves in them. Meanwhile, the Sandman guards alert Kracus to the humans' meddling. Kracus plans to get them himself.
On Gallifrey, Georgia tries to question Alverta on why he would work with the Sandmen, but he prepares to show her the unbelievable truth that he mentioned. Knowing she will not believe him, he takes her to the Matrix, the total of all Time Lord knowledge that he didn't destroy. He explains that he was casually hacking the system when he found the truth for himself. Capturing Georgia in a paralysis field, she appeals to him to spare her friends and David but he ignores her. Preparing to send her deep into the Matrix, he warns her that it will hurt.
Kracus enters the Sandman Carrier's storage unit where the three humans have disguised themselves as dormant Sandmen. After a lot of deep analysis of them, he decides nothing is wrong and is called away by one of his guards as they are reaching the Boundary. David tries to find a way out for the group.
In the Matrix, Alverta shows a pained Georgia the story that he has discovered, with both of them appearing in the projections of his story. He tells her of a demonic species called the Metastopheles, that go to random planets, and as a fetus is being conceived, they go into the womb and fuse themselves with the newly conceived fetus. The child is then always born on a day of tradition on the planet, due to the Metastopheles having "good timing". As the child is growing up, it always has coincidences surrounding it, and the Metastopheles inside feeds off those coincidences as it's growing up. Then if the host dies at a certain age, then the Metastopheles manifests, and uses it's energy it has gained to consume the planet it was born on.
Alverta is briefly interrupted from telling his story by the arrival of the Sandman Carrier over the Capitol. Near the Boundary, the Sandmen land to take down the humans, but they are distracted by Xe Hamo's weaponry which they quickly destroy. It falls to Ryan to throw a bomb at a large group of them and he succeeds, overcoming his nervousness due to his dyspraxia. However, one is left standing and he runs.
Kracus finally arrives in the Citadel and Alverta says he wants to help him. However, Kracus reveals his plan is to wipe out all organic life in the universe via the death particle, placed in his chest by the Morpherium. Kracus explains that his warriors will be controlled by the Morpherium, including himself, but Alverta is disappointed in the lack of imagination of simply making themselves AI puppets. Although Kracus is offended, he allows Alverta to use his Sandman-conversion processes. Alverta follows him as his consciousness deals with Georgia.
Alverta's story continues. He tells of a particular Metastopheles that landed on Earth, and went into a house, as a couple were having a "magic hug". It did what the Metastopheles were said to do, and a few months later, a child was born, on Christmas day. Alverta then says that the story is over for now. But with the story all but finished, Georgia asks what happened to that child. Alverta laughs, calling it obvious, and reveals that the child is, infact, Georgia herself. She cannot contain the revelation as the Matrix starts to warp around her.
Meanwhile, Ryan, Nathaniel, and Xe Hamo run from the Sandmen, grab what few guns they have and try to take a few down. Although a few are killed, one captures Nathaniel and gives the others ten seconds to surrender before he gets consumed by a Sandman. As the two arrive to surrender, the Sandmen's weapons fire, but they arrive to find four Sandmen stood over some collapsed ones. One takes its head off, revealing Garald inside, and the rest of her group appear as well.
Kracus leads Alverta to the Sandmen's storage inside the carrier, but he says that his orders will be given by the Morpherium. He tells Alverta that it will not vacate him while he lives, so Alverta calmly tissue compresses him, killing him instantly. The Morpherium appears in mid-air, Alverta admitting he thought he would be killed by the death particle. Keeping the miniaturised Kracus and his death particle close, Alverta proposes to be the Morpherium's "business partner" and it enters his body with the promise of absolute supremacy.
In the Matrix, Georgia wakes up in a projection of a vast green landscape with Alverta. She refuses to believe his story, knowing her history, but he promises that it is true. Alverta explains her real childhood did happen, it just was not the start of her life. Georgia doesn't want to be any more special than she already was. And she dosen't want a demon to manifest from her when she dies. Alverta just says "Too bad," and laughs.
Georgia wakes up in the Citadel as Alverta explains that, after he ruined the planet, he killed the Time Lords that escaped and froze their dead bodies just in case. Experimenting, Alverta decided to create a race of Sandmen made out of Time Lords, with the ability to regenerate, and his new Morpheus Lords, with which he will use to take over the universe, come to greet him. To test his theory, he orders one to shoot another and it collapses to the ground, dead. However, after a few seconds, it regenerates and returns to its rank. Alverta realises that he has nearly become "the Hybrid" of Gallifreyan myth, half Time Lord, half Sandman, standing on the ruins of Gallifrey. With Georgia still paralysed, Alverta leads off his new army, to go "break a billion billion hearts" and "unravel the web of time".
Back by the Boundary, David and the other humans reunited gather to visit Gallifrey. Of the seven of them, David volunteers to try crossing first and the group successfully lands on the alien planet. David swears that they will find Georgia and save her as she saved them.
In the Matrix, Georgia wakes up to find a vision of the Doctor, who is equally confused as to how she is there. Georgia asks if she is at the right age for the Metastopheles to manifest from her when she dies, but the Doctor says that he does not have the answers. However, he states that Georgia should not be limited by her past and should not be afraid of her future, but Georgia says that she still does not know how to stop Alverta. The Doctor tells her to focus on "the one thing he said that you didn't understand" and suggests she should blow the Matrix's mind. He vanishes and Georgia decides to overload the Matrix with all of her memories from her life, including Doctor Who. Finding her energy back, she focuses intently and her entire history of herself, her adventures and Doctor Who flashes before her, before the Matrix explodes.
Georgia collapses on the floor of the destroyed Citadel, freed but unconscious, as her friends' group finds her. She comes to and they share their new findings, deciding to destroy the Sandman Carrier, although Georgia admits it will not stop Alverta. However, Georgia remembers the one thing she did not understand - Kracus claiming he held the death of everything - and the others tell her the story of the death particle. With a plan to detonate it on Gallifrey then escape, Georgia locks on to Alverta's location using a device from Xe Hamo.
Around the Sandman Carrier, her allies set up bombs but cannot find Alverta. However, Georgia discovers Kracus's miniaturised body. Alverta makes psychic contact with Georgia, having laid her a false trail, but she tells them that they will meet in the Matrix Chamber alone. As Xe Hamo's bombs detonate early, the group, split in two, leaves as fast as possible as the Sandman Carrier blows up, destroying the Sandman Army onboard and foiling Kracus's plan to restore the Sandman Empire.
Escaping to the Capitol and finding a room of default and unused TARDISes, she programs one to take David and the refugees back to the 21st century. Xe Hamo has one hand-detonated bomb left and Georgia plans to use it on the death particle, destroying all remaining life on Gallifrey, including Alverta and Time Lords. Knowing she will die too, Georgia bids one final heartbroken farewell, telling David and the refugees to "live great lives", and despite David's frantic protests, leaves the TARDIS
In the Matrix room, Georgia meets Alverta, with his Morpheus Lords still in tow. He tells her that he will let her live to witness his victories and that the Morpherium lives in him now, believing to have broken Georgia. However, she tells him she feels the opposite: that she is so much more than she previously imagined. Instead, she pulls out the miniaturised body of Kracus attached to the explosive. Despite being goaded by Alverta to detonate it and become like him, she is unable to. However, Xe Hamo appears having left the TARDIS, explaining how he sent the Morpherium back through time and space and offers to take the death particle as penance for failing to suitably hide it. As Georgia sprints away, she escapes in another TARDIS as Xe Hamo triggers the death particle, the explosion consuming Gallifrey and everything on it.
Georgia's allies arrive on contemporary Earth in their TARDIS, which materialises as a detached house to blend in with the housing estate where it has landed, with them unaware of Georgia's fate. Georgia lands the other TARDIS, in the shape of a tree, in a quarry on the other side of Earth. She takes a moment to herself, extremely shaken by the events, before going back to pick up David.