We wandered around the eastern wards of Severalls. I’d done my homework and was able to talk about the history of the institution along with some of the more colourful tales of day to day life there. This was all eagerly filmed as we slowly made our way around the complex.

Martin was in his element. He had a magnificent backdrop for his film, superbly lit by the hot summer’s sun. As we rounded every corner, another view caught his attention: the endless corridors, the sun-washed wards, the eerie nature of dereliction and the emptiness of this vast collection of buildings.

"Have you ever presented before?" he asked. "No, why?" He’d quickly discovered that I could ad-lib, talk and walk, and take cues and direction; so he was soon working me as a professional presenter.

After shooting a lengthy piece in the subway tunnels, we emerged into the sunlit wards, and we paused whilst I answered a Q&A section. My answers eventually ended up as voice-overs for some of the parts of the complete film.

At one point we heard voices along one of the corridors. We froze and listened. Whoever (or whatever) caused the noises didn’t come nearer; perhaps they saw us and thought a film crew would surely have permission to be there, and so slunk away.