Drifting in Space

After accidentally finding themselves floating in the vacuum of deep space (see the previous story "The Woman Who Fell to Earth"), The Doctor and her new friends (Graham O'Brien, Ryan Sinclair and Yasmin Khan) are rescued by two spaceships which are competing in an intergalactic race.

Blurred and disorientated, Ryan is awoken from a pod by Graham in a dark spaceship, being piloted by Angstrom. She tells them they are on descent to the ‘final planet’, and warns Graham and Ryan to brace themselves. Meanwhile, on the other spaceship, Yasmin wakes up inside a MediPod outside of the control deck and walks in to find the Thirteenth Doctor arguing with the pilot, Epzo, about how to steady the crashing spaceship. The planet the spaceship was heading for is no longer in it's correct orbit - hence why they ended up floating in space. However, rescuing The Doctor and Yasmin has depleted the spaceship's fuel and so The Doctor suggests that Epzo ejects the back half of the spaceship so that they can make it down to the planet - which Epzo identifies as Desolation. Reaching the dead, yet hostile planet, The Doctor and her three companions try and determine where they are, while Epzo and Angstrom have a discussion about the other spaceships who failed to emerge from hyperjump.

Hearing an alarm in the distance, the group trek over the desert to find a tent at the bottom of a sand dune. Going inside to investigate they meet a strange man calling himself Ilin who The Doctor deduces, along with the tent is a long-distance hologram. Ilin explains that Angtrom and Epzo are the remaining two participants in the final Rally of the Twelve Galaxies. They are on the last leg and have to survive the dangers of the planet to reach a site known as the Ghost Monument before the planet completes a single rotation. The winner will receive a financial reward, of 3.2 trillion Krin, and be taken off the planet while the loser will be left behind, stranded.

Rescue

After Angstrom and Epzo are sent on their way, The Doctor insists that Ilin show her what the Ghost Monument actually looks like. Ilin reluctantly produces a hologram on the table. To The Doctor's joy, it's her TARDIS stuck in mid-phasing due to the damage it has suffered. Having discovered their way off the planet Ilin's hologram then disappears and The Doctor's group follow Epzo and Angstom outside as the tent also disappears. Joining the pilots in their race, The Doctor promises to get her new friends home once they have reached the finish line.

While her companions discuss whether or not The Doctor will be able to get them home, they approach a boat on a stretch of water. While Ryan and Graham look at the boat's engine – which does not seem to be working, The Doctor and Yasmin find that the water is infested with millions of flesh-eating microbes. Graham and Ryan then have a breakthrough repairing the boat’s engine and they make way across the water, using it to reach the ruins of a former civilisation. While Epzo and Angstrom go their separate ways, The Doctor and her companions explore the ruins. The Doctor is cautious when the readings on her sonic screwdriver aren't clear. While they all explore different parts of the building, Epzo trips a hidden sensor which activates a platoon of SniperBots.

Angstrom

While initially inactive, Epzo fires at one of the robots which then fires back hitting Epzo. The shot however, actives the rest of the robots which shoot at The Doctor and her companions. Running into an enclave, they find an inactive SniperBot and discover that everything in the perimeter is being used for target practice, including the shooting range in which they are standing in.

The Doctor uses the remains of the SniperBot to temporarily disable the others with an electromagnetic pulse allowing them to escape to safety and to regroup. During this time, The Doctor learns that Angstrom seeks the cash prize to save her family from ethnic cleansing by the Stenza, while Epzo is out for himself due to his upbringing to distrust others.

The Doctor is able to hack into Angstrom’s tracker and inputs the SniperBot's information which leads them to a hatchway that takes them into an underground tunnel beneath the ruins. There they discover an experimentation facility. While Epzo goes for a nap and everybody else explores The Doctor manages to sync Angstrom's tracker to the facility's computer. This enables her to discover an entire tunnel system mapped out, giving them the chance to navigate underground and so use the tunnels as a shortcut to the finish line so avoiding the threat that is on the planet's surface. They also discover a form of writing scorched into the floor, left by whoever ran the facility. Translating The Doctor uncovers some of the planet's history. The group learn that the facility was run by a group of scientists who had been captured, tortured and made to work, under duress to create weapons of mass destruction for the Stenza. The also discover that when any of the scientists died their bodies would be cleared up by cloth-like creatures called the Remnants.

Epzo

Meanwhile the Remnants of the scientists attack Epzo in his sleep, nearly killing him, but The Doctor, Graham and Angstrom hear his cries and manage to save him. Yasmin and Ryan then run in to tell The Doctor about the SniperBots who have gained access to tunnels forcing them to flee. As they make their escape the SniperBots shut down the life support in the tunnels, leaving them all with no choice but to go back to the surface where they find themselves forced to a gas-ridden area on the surface by more of the Remnants who encircle the group. The Remnants then start to coax The Doctor by cryptically referencing something from her past. Telling everybody to dig themselves into the ground, The Doctor kills the Remnants with Epzo's self-lighting cigar by igniting the gas.

By daybreak, the party have made it to the site of the Ghost Monument, where another holographic tent is situated. But Epzo and Angstrom can't agree on who really wins, so The Doctor has them enter at the same time and declare themselves as joint winners. Ilin is displeased by this arrangement but concedes nonetheless. However, to The Doctor's horror he refuses to take The Doctor and her companions off planet with the pilots. The hologram, along with Epzo and Angstom, then vanishes around them, stranding The Doctor and her three companions on the planet.

A despondent Doctor apologises to her friends for stranding them when she hears the TARDIS trying to materialise in the distance. The Doctor uses her sonic screwdriver to fully materialise it. Happy to be reunited with her beloved time machine The Doctor offers her friends a trip home as she promised.

Upon entering The Doctor is overjoyed to discover that the TARDIS has rebuilt and redecorated its control room in her absence. Graham, Yasmin and Ryan are in shock and awe at the TARDIS’s interior and the revelation that it is a time machine. With that, The Doctor starts the engines to take the others home, even having a custard cream biscuit dispensed to her from the console as the TARDIS dematerialises.