This story started out as one in which Jack was meant to feature less. Very quickly, however, it turned into a Jack story. I seem to have had a lot of story ideas that centre on Jack, rather than other members of the ensemble cast. I need to redress that in coming weeks, but meanwhile, this is another Jack-centric story that sees our hero hurt physically and emotionally in the name of duty.

The idea of four dead students and a teacher in a high school is admittedly, a bit emotive to begin with. The allusions to ‘Cardiff Columbine’make it clear why that is. It doesn’t happen often in British schools. It’s easier to think ‘this is a story, it can’t really happen’. I probably wouldn’t have written this story if I was writing in America for a mainly American readership.

Initially, I wanted a story in which a vulnerable young adult was displaying unusual and dangerous abilities. The story was going to centre much more on the team being suspicious of Bryn, convinced that he was an alien in disguise and subjecting him to tests such as that used on the character Beth in the TV episode Sleepers. But as I began to write, I found that this aspect of the story became less vital. It began to be more about Jack's friendship with the boy and how desperate he was for somebody to trust.

Bullying was another aspect which I had not originally intended to focus on, but which, as the story developed, took on a new dimension. The boy, Bryn, and his strange special ability that allows him to electrocute people who hurt him, is the ultimate bullied child getting the ultimate revenge in some ways. The important thing, of course, is that Bryn isn’t in any way triumphant about what he has done. He is horrified about the deaths, even though the people he killed had been cruel to him. But he isn’t a monster who would use his ability to go on a killing spree.

The scene in the changing rooms was actually one I knew would cause a certain amount of comment. In the middle of writing that part I had to go out, and as I was walking up the road I was thinking about how people might view it – a forty year old gay man alone in a changing room with a vulnerable fourteen year old boy. It was a scene that had to be approached carefully. But that is why the boy goes behind the rack of coat pegs to get changed and why Jack changes his own clothes separately. Of course nothing untoward would happen. I’m certainly not writing that sort of story. All that scene was about, was enforcing the fact that Bryn trusted Jack when he had no reason to trust anybody.

Trust, of course, is the main point of the story. Bryn, a frightened, very vulnerable boy, gives his trust to Jack. And then Jack has to break that trust, hurt the boy, in order to ultimately save him. But I am sure anyone who has read the story properly will have grasped that. The point doesn’t need hammering in.

The conversation Jack has with Bryn at the end, was slightly amended between the first and last draft, influenced, in fact, by John Barrowman’s documentary ‘The Making of Me’ in which John talked about and set out to prove, his conviction that he was born gay, that it is genetic, and that if he wants to be happy, then he has no choice but to be gay. In the original version of the story Jack told Bryn that it would be his choice when he was old enough to decide. But that contradicts the way John Barrowman, and presumably, many gay people, think about it. It isn’t a choice as such. It is a matter of following his heart and living the way that feels best. It is a subtle difference, but after seeing that programme I did feel it needed a bit of alteration. I think the revised version rather more reflects Captain Jack as portrayed by John Barrowman, who has always said that there’s a lot of John in Captain Jack. In any case, I like John and respect his opinions and I hope my version of his character is one he would be happy with.

Yes, that last little sequence, when Jack gets into Garrett's car and tells him his day was 'absolutely shocking' is a TERRIBLE pun. But I just can't think of taking it out. It does round things off quite neatly. You'll all have to just grin and bear it. Meanwhile, the next story is also Jack-centric, but I WILL get back to the rest of the team eventually.