"It's like trying to do a Rubik's Cube in your head" – Charlie Brooker breaks down how Bandersnatch was made

In the videos, Brooker admits that figuring out the film's "myriad" of alternate versions of events was "very challenging at every stage", comparing the process to a Rubik's Cube.

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"There were points where in working stuff out, it got like trying to do a Rubik’s Cube in your head, and I literally had to get up from my desk and kind of walk around the house holding my head," he said.

"When I started out, I thought, ‘Well this will be fairly straightforward, I’m sure I’ll have to draw a flow chart at one point.’ Cut to several months later, it kind of exponentially started to balloon."

Netflix's choose your own adventure technology had been used for simple children's stories, but this was the first time the streaming service had attempted to tell a feature-length, adult story using the format.

New software was developed to keep track of the episode's various possibilities, according to Todd Yellin, Vice President of Product at Netflix.

"To really understand how it all fits together needed whole new tools to be invented," he explained.

Brooker and the show's producers began using software like Twine and Branch Manager in order to keep a handle on the unwieldy, expanding timelines, a method that producer Russell Mclean detailed in an interview with Wired.

Brooker added that the actors also had a tough time "having to keep track of where their character is, bearing in mind that the previous morning they may have played themselves in a different timeline".

Dunkirk's Fionn Whitehead, who plays Stefan in the film, agreed: "It’s really hard to get your head around which scenes you’re doing, because there are just so many."

Will Poulter, who plays genuine game developer Colin, joked: "Sometimes I’d be delivering what I thought was version three of the dialogue and I can see the actor opposite me giving me the eye as if to say, 'That’s version four, mate!'"

Brooker also admitted that when Netflix first approached him about potentially developing an interactive film, he wasn't keen on the idea.

"My initial thought was “No, I don’t want to do that'," he said. "And then annoyingly I had an idea that would fit."

In one of the videos, producer Annabel Jones added that she and Brooker were initially cautious about agreeing to the idea, as they were nervous the interactive element would be "just a gimmick".

However, as we now know, it all worked out — and it's "very, very Black Mirror", according to Brooker:"It’s got a lot of different Black Mirror instruments playing all at once and it does feel that it works."

Black Mirror: Bandersnatch is available to stream on Netflix now