At first Amy believes that they can just use the TARDIS to go find him, as they did before. The Doctor sadly explains that they can’t as the resulting paradox will blow New York in half. Amy is so distraught by this that she chooses to be touched by the Weeping Angel as well.
This was a good, if heart breaking, way for the Ponds to leave the Doctor. Realistically Karen Gillan and Arthur Darvill wanted to leave the series so their characters needed to be written out.
In our own campaign you are not restricted by this fact. If your players enjoy inhabiting the roles of Amy and Rory and want to continue having new adventures (and not just ones set in the gaps of previous episodes) you need to diverge from the television series here.
The important thing in this scene that the Doctor hasn’t given up hope entirely. He asks Amy to back away from the Weeping Angel and rejoin him in the TARDIS where they can work out what they can do.
This could have just been a ploy to keep Amy with him, just as he tricked Rory in ‘The Girl Who Waited’ but there have been plenty of instances where things have seemed hopeless only for the Doctor to come up with brilliant plan, if he is given time.
This should be the starting point of the diverging adventure. The Doctor, Amy and River Song are all in the TARDIS. How do they save Rory without causing a destructive paradox?
The first option is to follow a similar gambit to ‘The Wedding of River Song’ and create a situation in which the requirements of a Fixed Point are met while giving them the wriggle room to make a miraculous escape.
In this case it is the gravestone which convinces the Doctor that Rory has to die. Many on the internet have pointed out that as long as they arrange for the headstone to be placed in the graveyard it doesn’t mean that Rory has to be buried there.
If you are looking for a simple solution this could be a quick way for the characters to be reunited with Rory. It does seem anti-climatic and makes Amy’s sacrifice in the actual series seem silly.
A second option is that they can collect Rory as long as they eventually return him to New York to die, or at least have his body buried there. You may wish to use River Song’s Vortex Manipulator to navigate any temporal distortions for this.
This can add tension to Rory’s subsequent adventures, since if he should die he would take half of New York with him as the resulting time paradox is unleashed. Would the Doctor allow this or would he have second thoughts and try to take Rory back earlier than planned?
The group might decided to find a replacement for Rory, either to travel with them or to take his place in New York, so some version of him will still die there. Past versions of Rory are possible but still run the risk of paradoxes should something happen to him.
They may find a way to recover the dying old Rory from Winter Quay. It could be that the paradox sent it into the vortex, giving the time travellers a slim chance to recover that Rory and take him back to New York to die. Given that the gravestone apparently existed prior to the destruction of Winter Quay this would seem to satisfy the Fixed point in Time.
‘The Rebel Flesh/Almost People’ introduced the concept of gangers and revealed that Amy had been unknowingly operating one for quite some time. This could lead them to return to that time period to obtain the same technology and bringing it back to Rory in New York.
While he might have to remain in that time period to prevent a paradox he could remotely control a ganger body no matter where in time and space it might go. It would be a strange set up but Rory could even return to a normal life in the 21st century.
The big problem is the energy released by the paradox. In order to save New York the Doctor might be able to find away to deal with this energy, preventing further destruction. Luckily there are some options.
‘Sound of Drums/Last of the Time Lords’ showed how the Master created a Paradox Machine to allow the Toclafane to decimate the Earth, and their ancestors, without wiping themselves out.
The Doctor could construct a similar machine. While the TARDIS is the best candidate it is possible he could use something else, maybe gathering parts from a TARDIS graveyard similar to the one seen in ‘The Doctor’s Wife’. This would be an exciting adventure in itself, especially if there are other parties after similar vital parts.
The drawback is that the Paradox Machine would have to be well protected because should it ever cease functioning New York will be destroyed. It could be that it only needs to be activated when they want Rory to leave the time period he is stranded in. Once they return him they can turn it off until the next time.
They could try to funnel the energy away from New York, for example into the vortex or through a worm hole to an alien planet. If you wish to tie everything together you could have the energy funnelled into the heart of the TARDIS.
The time machine could then shunt that energy into its earlier self. ‘The Doctor’s Wife’ suggested that areas of the TARDIS exist in multiple time periods. Of course the resulting burst of energy would cause the TARDIS to explode but then the Doctor has already solved that problem.
This could be the explanation for what caused the destruction of the TARDIS in ‘Pandorica Opens’ and the subsequent release of time energy. It would turn out that the alliance of aliens were right to think the Doctor was responsible, just that it was a future version of the 11th Doctor.
What ever option you choose your campaign can continue with the Doctor, Amy and Rory. It never has to end.