Charlie Brooker - Inside Black Mirror

Joel Collins (series production designer):I came up with the idea of roaches looking as though they had hydrocephalus, as if their brains and everything had swelled. We wanted them to look scary and angry, but we also wanted you to feel sorry for them later.

Lucy Dyke:Our make-up designer Tanya Lodge brought in Kristyan Mallett, a prosthetics designer whose credits included The Revenant and Everest . We tested four shortlisted designs on camera. After a few tweaks, we and Netflix agreed on the look, but the eyes were still too human. Tanya then used full-eye black contact lenses on the adults, but we needed to VFX the boy’s eyes later on.

Annabel Jones:Our reveal was that the ‘roaches’ the soldiers saw were just humans. So, for the story to hold, we would have only ever been able to show the roaches from the soldiers’ POV. This would have restricted us cinematically, so we decided we needed the roaches to look normal from the back. We shot the first fight sequence in the farmhouse very frenetically to help obscure this.

Jakob Verbruggen:The roaches had to move a certain way, so that was mainly a combination of actors and stunt people, with a few dancers too. We created a kind of choreography.

Natalie Ward (costume designer):The roaches had become like lepers in a society they were once part of. We decided they would take clothes and food from villages to survive. Nothing was meant to fit them, so they adapted things they found and wore clothes for protection against the cold. Even though we didn’t see that much of them in the end, it was really important to me to make everything look believably distressed.

Lucy Dyke:The roach prosthetics required several hours in make-up, so any bad falls, scratches or nicks could see our actors sent back to the chair for several hours. We had 18 days to shoot the entire film, so the pressure was really on our actors to get it right. Malachi not only had to deal with an incredibly difficult performance, a complicated fight sequence, using weapons and very delicate prosthetics, but he was also literally shooting film using his MASS system! He did it all without breaking a sweat.

Charlie Brooker:I don’t think we made the dream sequence element of the story clear enough, but the soldiers are given these sexualised dreams as a reward for doing well on the battlefield. There’s some combination of mind control and augmented reality going on, but we never sit you down and tell you. After Stripe kills the two roaches, and his implant is malfunctioning, his reward-dream goes wrong and suddenly there’s three of the same woman.

Jakob Verbruggen:To create multiple versions of Stripe’s fiancée, we had this choreography where we had the actress Loreece Harrison and then body doubles with the same hair, clothes and skin tone. So everything was real and in-camera.

When Stripe learns the truth about the roaches and tries to rebel, he finds himself in a room with his quietly spoken psychologist Arquette, played by House Of Cards ’ Michael Kelly.

Charlie Brooker:Arquette was always written to seem sympathetic, but in my original version he was probably a bit more stuffy, or more of an old-school psychologist. Michael Kelly brought a lot to the role. He’s very good at doing likeable warm menace!

Jakob Verbruggen:Arquette is a father figure to some of these soldiers, including Stripe, and believes he’s doing good. Even in the final scene, I think, there’s a fatherly element to Arquette. We always decided not to demonise him too much. Maybe he represents evil, but he believes in his cause.

Charlie Brooker:While quite a few people find this episode’s twist pretty obvious, there is a complication. The soldiers literally see the roaches as monsters but the villagers don’t – they just consider roaches to be monsters. It’s easy to miss, but we explain in passing that the villagers don’t have this MASS system in their eyes. So the soldiers need the system to allow them to kill people, but the public don’t need that to demonise and hate people.

The title Men Against Fire came from S.L.A. Marshall’s 1947 book Men Against Fire: The Problem of Battle Command , which talked about the low percentage of soldiers who actually fired their weapons during the first two world wars. And so what Arquette tells Stripe has some basis in reality. I was struck by the effort the military has to go to. The problem is that people don’t want to pull the trigger, so what’s the solution? Dehumanising the enemy.

Arquette has a lot of speeches to do, while explaining to Stripe what’s been going on. There’s generally a bit too much of things being explained to Stripe slightly after the fact. I should have found a different way to achieve that.

Annabel Jones:Charlie’s being too hard on himself. Men Against Fire is one of our heavier films thematically. When you’re making an anthology and it’s going to sit aside films that are pure entertainment like Playtest , then it might appear more expositional, but I think it’s a profound film. For a hi-tech world, I love the fact that the end of the film consists of two people in an empty room discussing ideas of right and wrong.

Jakob Verbruggen:We put Stripe and Arquette in a bright, uncomfortable and extremely claustrophobic room and decided not to have both actors in the same frame. Hopefully that resonates with the audience. And then, when Stripe learns the whole truth, the shape of the room seems to change, because it closes down on him.

In the final shot of the film, Stripe returns home to be reunited with his fiancée, but all we can see is a derelict, abandoned house.

Annabel Jones:Arquette revealed that, when Stripe signed up for the military operation, he knew what he was agreeing to. To enable him to return home, Stripe has agreed to have his memory of the event wiped and the military have won. Stripe’s tear is a hint of him having a sense of this. We intercut MASS’s idealised version of the homecoming – white picket fence Americana with the sweetheart on the porch welcoming him home – and the reality of a run-down empty house covered in graffiti. The propaganda, military and personal, continues.

Jakob Verbruggen:Everybody can make their own interpretation of our ending, because that’s the only thing that hints at the society, or world, where the story takes place. What has happened? Is anything real? Was even Michael Kelly’s character real? Is this just a story about a soldier dealing with PTSD? Who knows?