Ransom was written primarily because I had too many stories about Davie coming up and really wanted to ring the changes a little. Feedback about previous stories centred on Sukie and Vicki has always been positive so I decided they needed a field trip with a crisis.

I didn’t intend to set the whole story on the coach. At first it WAS going to be aliens who kidnapped the school group, but I couldn’t think of a good reason for them to do that. It was far more likely that ordinary humans would do something like that for money – the very motive The Doctor hates the most.

The story was originally going to be set in Scotland, and the psychic blackspot would be on the border where the Daleks had been especially busy during their invasion fifty odd years before. I decided against that because I really am not familiar with the Scottish border area. So the story ended up being set in Wales. That actually made the place where the coach was concealed make more sense. Wales has lots of disused mines, thanks to Thatcherism. Sukie’s comment that they ‘used to have coal mines here’ struck a cord with a lot of Welsh readers. Although I am surprised nobody picked up on the slightly Enid Blyton element to enclosing them in an old narrow guard mine railway tunnel.

The psychic blackspot, of course, was there in order to make the rescue more complicated. Otherwise, they could have made telepathic contact with The Doctor or Davie and Chris and been rescued in a very short time. Having to rely on Sukie’s email connection to her 26^th century friend, Earl, was a way of extending the tension a little bit.

The paranoia about Vicki being an alien reminded a lot of readers of the Doctor Who episode Midnight. The fact that this story is set on a coach in a confined space, much like the space bus of Midnight allows for the same kind of disconcerting situation to arise. But actually, it never even occurred to me until it was pointed out. I was just looking at a way of exploring Vicki’s alienness as perceived by her school friends.