Time After Time started with the fact that I hadn’t done a story involving Sian and Louise for a while. In fact, they never seemed to be anything but opening hooks for the two stories, The Vabatheth and Identity Theft. I really wanted to focus on them a bit more.

Then I had an idea about some kind of time slip into the period when Estelle was young and living in the house Louise and Sian live in now. The idea of Jack falling back to the Second World War along with one of the women and meeting up with Estelle then occurred to me. It would allow Jack to renew his love affair with her briefly.

All fine and grand so far. But then I mulled over several ideas. One of them was that Sian would actually be murdered by somebody in that era and that either Jack would murder the murderer and then be arrested for doing it, or be arrested for Sian’s murder by mistake. Either way he would subsequently face execution by hanging, as would have happened in those days. Obviously he would then come back to life and disappear for sixty years before coming back to explain what had happened to Louise.

But that was just a bit too nasty even for a Torchwood story. How could Jack possibly return to Louise and tell her that Sian was dead?

I also had the idea of Jack and Sian disappearing together, possibly to America, and living together as a couple – though non-sexual, of course. Sian would obviously die of old age, but at least loved and cared for by Jack. Again the problem was breaking the news to Louise once the time came around again.

So, finally I decided that Sian would not be murdered or raped, but she would accidentally kill the man who tried to do both. Jack would cover up the murder and then go to Torchwood and demand help for them both. Sian could be frozen, to be revived at just the right moment to get back to the house and make sure everything is all right. Meanwhile, Jack has to disappear.

At this point, as many readers pointed out, a completely different part of the story began. I actually contemplated making it a two parter, but somehow I didn’t think the story of Jack living through the rest of the twenty-first century in various different lives under different names, made a story in itself. It worked better as a section of the same story.

His ‘homecoming’ as James Holden of Byron, Illinois, is a slight homage to the 1993 film, Sommersby, in which a man who ‘returned’ from the American Civil War was almost certainly an imposter but settled into the life of the man whose place he had taken. Jack does that in a nice, harmless way, as almost blind Mrs Holden’s son who has returned from the war. The other, rather shorter stories, portray him as a serial drifter through the decades. Of course, its fairly obvious that he chose names with the same initials – JH – every time.

Finally, Jack Harkness comes home. And I had to round the story up. There was going to be a complicated bit here involving Gwen getting there a split second earlier and stopping Jack from opening the box – thereby making none of it happen at all. But I decided against that and went for the simple version where Jack, Sian and Ianto arrive at the house and are the reason Louise and Gray were out of the room when Jack and Sian were pulled into the time anomaly. They then discover that the box was a once only trap, set up by the Trickster. This is a bit of a cop out ending, perhaps. The Trickster, a character first used in Sarah Jane Adventures, and then in Doctor Who, is a catch all solution to situations like this. It explained why such a strange and pointless trick was engineered just to catch Jack Harkness.