Charlie Brooker said the basic idea came in 2004 while watching 24, when he thought the show's terrorists moved in waves like Space Invaders and joked they might as well be zombies, which led him to imagine a zombie apocalypse breaking out during a Big Brother filming.

Brooker wrote the first draft of the script in 2005 during the airing of Big Brother 6, basing some fictional housemates on real former contestants: Maxwell Ward and Saskia Howard-Clarke inspired Marky and Veronica, while Pippa and Space were loosely based on Helen Adams and Kieron 'Science' Harvey.

For research, Brooker attended the live eviction of George Galloway during Celebrity Big Brother 4 and visited the camera runs surrounding the real house; he also cited zombie films like Romero's Dead series, Zombie Flesh Eaters, 28 Days Later and The Walking Dead as influences.

The eviction scene for Pippa was actually filmed at the real Big Brother house in Elstree on 18 July 2008, the same night Belinda Harris-Reid was genuinely evicted from Big Brother 9, with actress Kathleen McDermott 'evicted' in front of the live audience and filming an improvised eviction interview with Davina McCall in advance.

Several former Big Brother housemates were filmed as themselves in a fictional reunion scene, with the production then separately recording their reactions to the fictional zombie outbreak.

Davina McCall's zombie scenes were all filmed in a single day; the bodies in the corridor sequence used special-effects dummies, except for one that McCall is shown eating, and a dummy of her was used for some shots since she was only available for one day.

McCall said she was left bruised the day after filming from repeatedly hammering on a door, and based her zombie running style on the T-1000 from Terminator 2: Judgment Day.

Budget and time constraints affected production: extras were sometimes redressed to play multiple zombies because of the cost of contact lenses, a planned explosive car crash in episode 2 was scaled down to a simple breakdown, and an original concept for the finale set six months after the outbreak had to be dropped; many crowd-scene zombies were volunteers recruited online.

Charlie Brooker has a brief cameo as a zombie in the second episode.

The fictional Big Brother eye logo used in the series was designed as a combination of several logos used across the real Big Brother franchise, and the set replicated the real show's cameras, two-way mirrors that could conceal the camera crew, astroturf, and a modified Diary Room chair from Big Brother 8.

As part of the promotional campaign, a map of the Borehamwood region (site of the real Big Brother house) was added to the browser-based game Urban Dead, alongside an interactive Diary Room clip where a blood-covered contestant appeared to write the viewer's entered name on the wall; this campaign later won a BAFTA Television Craft Award for Interactive Creative Contribution.

Simon Pegg criticized the series in a Guardian column for its use of fast-moving zombies, calling such creatures 'bereft of poetic subtlety'; Brooker responded that the zombies had to run for the story to work and that running zombies were cheaper to produce than stumbling ones.

In 2013, the fourteenth series of Big Brother featured a quarantine-themed task involving a fictional viral outbreak reportedly inspired by Dead Set, and Brooker noted the production team had checked with him that he didn't mind the reference.

Brooker has said Dead Set 'contains all of Black Mirror's DNA,' and retrospective commentary has described the miniseries as a thematic precursor to his later anthology series Black Mirror.

A Brazilian adaptation titled Reality Z premiered on Netflix in 2020, and during the COVID-19 pandemic, media coverage of Big Brother contestants emerging from isolation into a changed world drew comparisons to Dead Set's premise.