That was the plot that I initially took to Russell. He’d deliberately not re-read the book, while both Julie Gardner and script editor Helen Raynor had read it. His first batch of notes, and actually every batch subsequently, sent us back to the book, until we were working on a straightforward adaptation. And that’s when things fell together and started to work.

The first issue to deal with was the Doctor’s motivation. In the novel, it’s left unclear why exactly he’s done this to himself, though there’s a dirty great hint that it’s to share and understand Benny’s emotional state. We needed a driving force that would provide a pre-titles sequence. So we settled on the chase set-up, and, after a few meetings, we decided that the aliens would have a short life span, so the Doctor hiding from them wasn’t a cowardly way out, but an act of mercy, mainly to the worlds the aliens would devastate in a normal pursuit, but also to the aliens themselves.

The scarecrows came from Russell. The aliens were shape-changers, and looked like people. So a monster was needed, so ‘how about some scarecrows?’ I’ve never heard them called ‘Jack Straws’ apart from in that interview with David. I think it’s a Scottish thing.

The biggest continuing debate was about the pod where the Doctor keeps his Doctorishness. Was it going to be a cricket ball? Another Russell solution: a fob watch. Not just because of the Time Lord symbolism, but because a fob watch has a door you can open, an easy something that John Smith can choose to do or not to do. Did splitting the pursuit of the ball away from the aliens’ pursuit of the Doctor mean two awkward, disconnected stories, as Julie for a long time thought there might be? The danger was certainly there, but we fixed it to her satisfaction, which is always the thing worth doing in production meetings. Julie has a way of knowing what viewers will get and what they won’t.

One of the last things that got sorted was the time frame. For many drafts, Smith’s courtship of Joan was played in dissolves of days and weeks. But it took the immediacy out of the aliens’ pursuit, and left them looking rather useless. They became lovers, for many drafts, but without the many weeks, such a swift intimacy would be inappropriate for 1913. I think the flash forwards to the couple’s future together give us that flavour of time passing.