We all survived. Steven is a finer Steven than before: despite a week of negative Twitter speculation reported disingenuously in the Sun, he really did do it and he really is a better man for it.

For those wondering what has happened to him since, Steven now works as a teaching assistant in a special-needs school, a job he finds much more rewarding than the series of positions he held before. And I think in time he’ll make an excellent teacher. For now he’s keeping his Twitter and FaceBook set to private, but I’m sure before too long he’ll open them up and you’ll be able to ask him about his experience.

The show was, as many of you spotted, The Wizard of Oz with zombies. Our Dorothy (you’ll have noted the Kansas Autos sign on our mechanic’s van who visits Steven’s house) did not seek a place over the rainbow, but nonetheless had to learn that there is no place like home. With some extra motivation and carpe diem thrown in: L. Frank Baum’s message that you don’t need to go looking anywhere further than your own back yard always struck me as a little limiting.

After the tornado/apocalypse, our Dorothy encounters Leona – of course a cheap play on ‘lion’ – to discover courage and responsibility, a scarecrow (Iain) who becomes indecisive and necessitates a new alpha-male in the group, and a tin-man (Danny) who, having no heart, makes it necessary for Steven to find his own. The Yellow Brecon Road awaits to take Steven to salvation, but it is Oscar Zulu from Emerald Communications – the wizard (ahem) behind the curtain – who provides the noisy, army equivalent of his hot air balloon to take them away. You’ll have spotted the graphic on the side of the helicopter.

Like Dorothy, Steven is left behind: before he can return home he has to say what he has learnt from his experience, and what he has known all along. Which he does, movingly, in the video tape he makes for his family. To encourage this moment, we had him see the others do the same and held the camera held back from him until he was ready. That done, and his lesson learnt, cue the deus ex machina of the phone call (I know now I should have floated down in Glinda’s bubble for absolute authenticity) and he’s magically transported back home to a life now dramatically reassessed.

Writing a show with an unscripted, unwitting central character is a strange and demanding task. My co-creators Iain Sharkey (himself a freaked-out participant in my Séance programme many years ago where we first met) and Stephen Long worked on the idea with me in the first instance, before Mark Gatiss got involved to help find possibilities for narrative. The massive bulk of the extraordinary writing task was then shared by Iain and a gifted, lovely writer called Ben Teasdale, both of whom gave heart and soul to the project. Sharkey can be seen starring as the first we see of the ‘infected’, behind the window in the red tag building. His condition of butt-nakedness-save-for-a-backless-hospital-gown was sadly lost in the gloomy lighting of the sequence, but I’m sure it added to Steven’s growing sense of deathly horror.

For my production team to make it all happen took a level of dedication and love almost unheard of in the industry. Working 30 days without a break, spending nights awake in Steven’s shed waiting to pull a plug to his television, they were stretched beyond anything one would expect anyone to put into making a television show. Samuel Palmer and Dave Struthers in particular – both brilliant and talented core members of our little family – deserve special mention here. Dave’s Twitter feed over the last week was a tirade of fury at the glib, uninformed assurances of fraud after the endless work he and Sam put into the hugely demanding job of secretly filming Steven over such a long period of time. I bow to the extraordinary level of commitment and resolve shown by the whole team, who were bonded above all by a desire to do right by Steven. It was a formidable show to make.

And it’s not over yet. Next week brings two more shows under the banner Derren Brown: Fear & Faith. In part one, airing this Friday at 9, we follow the first members of the public to take a wonder-drug, developed for the military, that completely eradicates the experience of fear. It was another astonishing journey. I hope you enjoy it.