With a solar flare approaching the Doctor and Clara believe that this is the end of humanity in ‘In The Forest Of The Night.’ This time the Doctor believes that there is nothing that he can do, that he can’t fight physics.
As in ‘Kill The Moon’ Clara points out that they’ve seen the future but the Doctor indicates that those futures are about to be erased. In that previous adventure the Doctor suggested that there are moments in which he can’t see the outcome, moments when everything else gets decided.
We must assume that this is another one of those moments but this could indicate that the time is a lot less fixed than we thought. The Doctor might only occasionally know if history is about to change completely around him.
While ‘In The Forest of The Night’ doesn’t depict the end of the world we know that Earth does have a finite history. Why not have the world end in 2016 or some other point in the near future?
One advantage of this is that you don’t have to attempt to make the future of Earth believable because it doesn’t have one. If you do wish to run adventures in a futuristic setting there are many advanced civilisations elsewhere with human looking aliens that could fill those roles.
Time travel would become much more important to the player characters. No longer is it just a way to take them to interesting places it has saved their lives by letting them avoid the inevitable.
In this episode the TARDIS is described as a life pod. The crew are therefore cast in the roles of survivors, possibly the last of their race (at least when they are in a time period after the destruction of Earth).
This would also recontextualise the future. The days after doomsday are something that humanity would never be able to see normally. The very fact the PCs are there is a source of wonder but also sadness.
Removing humanity from the equation would give you the freedom to explore a completely new future without them. How does the universe react? Will another race fill their role in major galactic events? Can the universe cope without the resources that Earth possessed that attracted so many invasion attempts?
Knowing when and how the world is going to die could change how PCs behave. They might wonder what is the point of saving the Earth or single individuals, especially close to doomsday, if they are only going to die. Adventures could show them that any amount of life is precious.
Clara persuades the Doctor not to save the Coal Hill School children because she thinks they would miss their parents and fears the Doctor would just abandon them on an asteroid. This scenario is extremely short sighted. Setting aside that this is a choice between life and death she also forgets that the TARDIS is a time machine.
The planet might not be able to be saved but humanity could be (or some small part of it). The TARDIS gives PCs as much time as they need to save people and take them somewhere safe.
This could form the basis of an ongoing quest. PCs could search the universe for a new home for Earth. There are plenty of planets that might be similar but have their own unique problems, from differences in environment to proximity to other inhabited worlds.
Will they choose an isolated planet rich in resources or find an inhabited world whose natives can co-exist and even help colonists rebuild? Will they select a time period in the past or at some point after doomsday?
Once they’ve selected a new home who do they choose to save?
The obvious candidates are friends, allies and family but are these the best people to build a new life on an alien world? Would they appreciate the PCs whisking them away to toil and struggle on distant planet? Would they even believe that there is a doomsday?
PCs could approach governments or other large organisations to make the preparations for the exodus. They might travel back several years to allow enough time to put a plan in place and gather required resources. During this period the PCs might have to make sure that the secret isn’t reveal, causing wide scale panic.
With enough co-operation the PCs might be able to arrange for a large number of people to be rescued. The interior of the TARDIS is supposed to be quite vast, meaning that whole cities or countries could be saved, if they can pass through the threshold of the time machine in an orderly fashion. The PCs could make several trips to get everyone they can.
This could be version of Operation Golden Age in ‘Invasion of the Dinosaurs’. If the PCs don’t mind altering history (and why should that matter given the Earth is doomed?) they could take over that ruse for themselves.
If you did want to base this scenario around ‘In The Forest Of The Night’ a mass evacuation, engineered by the PCs, could explain why London was so deserted. Only small pockets of people would be left, possibly missed during the exodus.
The PCs aren’t restricted to people from the present. There could be historical figures that the PCs believe would be perfectly suited for helping a colony flourish. Those from the past mind be even be better suited to coping with primitive conditions and basic tools. It could turn out that the PCs are responsible for several famous disappearances throughout history.
Now they have a new planet and people to colonise it the PCs can become their protectors. They could live alongside them, dealing with logistics and helping them overcome any challenge they encounter.
Alternatively the PCs could jump ahead, checking in and always appearing just when they are needed most. This approach allows you to flesh out the new timeline and show how the colony is expanding.
The PCs could wait until the New Earth is well established before collecting the remainder of survivors from before doomsday. These stragglers would find a new world, already controlled by fellow humans.
There have been several episodes that indicate humanity has a great nostalgia for the past and have a habit of emulating past places and fashion. This New Earth could be much like the old, to the extent that historical events might happen again naturally.
PCs could discover, possibly by consulting the TARDIS travel logs, that they’ve come to this duplicate Earth (which they helped create) in the past mistaking it for the original. This could be a handy way to explain any past historical mistakes or establish that all adventures set in the future of Earth were actually occurring here.