Warning: contains major spoilers for The Referee’s A W***er.

The final reveal of Inside No. 9’s brilliantly packed series five premiere is a tattoo and a smile.

Having presided over a total disaster of an end-of-season match (corrupt officials, brawling players, abandoned play), head referee Martin Rutherford has just watched his spotless professional reputation go down the drain. He’s now a football villain, hated by fans, hunted by the press, spurned by his lover and facing the ignominy of a retirement basked in shame.

And yet, he smiles. Dropping his changing room robe, we see why. The words ‘City Til I Die’ are tattooed across his back. Everything that’s happened, he’s orchestrated. The corruption, violence and chaos were all part of a careful plan to ensure that the league winners would be demoted, ensuring promotion for his team – City.

When David Morrissey (The Walking Dead, The Missing) read the script, he accepted the part of Martin with one proviso, co-creator Steve Pemberton tells the crowd at the Inside No. 9 series five launch:

“Dave Morrissey had been saying to us for ages that he would love to be involved […] I was doing Britannia with him and I was telling him about it and I could see a little glint in his eye.

In the original script, the two teams – we didn’t want them to be real teams, they had to be fictional – we just had City and Rovers, and the team he supported was United and it had on his back ‘United ‘Til I Die’. Morrissey, being a big Liverpool FC fan, said ‘I’ll do it on one condition. I’m not having that tattoo on my back’, so we had to change all the teams round to suit him. It was worth it, worth it to get him!”

The Referee’s A W***er, Pemberton explains, grew out of a one-line idea “that started with the notion of where it could be set.”

“The referee’s changing room is a space that most of us probably don’t think about very often but it struck us as a really interesting idea to set an episode there. Also, it’s very useful with Inside No. 9 to have a pre-ordained structure so the idea of before the game, half-time and then after the game gave you a really good structure for an episode. It was a different number nine to be inside! The first living no. 9!”

“Once you start thinking about football and what are the stories to do with being a referee – the corruption, gay footballers – just what it’s like from a personal point of view to live with the abuse. There are lots and lots of stories. Watching it now, I’m amazed how much we packed in to 30 minutes.”

Pemberton, a football fan, was “the driving force” behind the episode, says co-creator Reece Shearsmith, “I just learned it like phonetically,” he tells the crowd to laughter. It was absolute gobbledegook!”

Later in this series, the roles were reversed as Shearsmith led the writing of an episode about his personal passion, the world of magic and illusion. Misdirection, directed by Guillem Morales, will air on Monday the 24th of February at 10pm on BBC Two.

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Read more about Inside No. 9 series five here.