This hour-long 'film' is the story of two young lovers - Ash (Domhnall Gleeson) is permanently glued to his mobile phone - something most Black Mirror viewers can relate to in this age of tweeting as an accompaniment to TV watching.
When Ash is killed in a tragic traffic collision, his girlfriend Martha (Hayley Atwell) learns of a new service that gleans traits from Facebook, Twitter, e-mails and other online profiles to replicate a lost loved one's personality.
Though she's hesitant to use the software at first, the revelation that she's pregnant sends Martha spiralling and soon she's embracing one upgrade after another until Ash - or at least a replicant - is back, walking and talking, at her side. But it's not really Ash - the replicant is hollow, without a soul - and so much of what made Ash the man he was, and the intricacies of his and Martha's life together, is lost in translation.
'Be Right Back' has a neat sci-fi idea at its core, but there's more to this drama than just a nifty gimmick - Ash and Martha's relationship, with its friendly bickering, car sing-a-longs and awkward sex, feels so, so real. It's clear that the cynical, snarky Brooker has been hiding his soft centre, since he has such a terrific handle on relationships and modern romance.
His dark streak isn't entirely absent though, with the film's latter half cruelly mirroring all that we saw before; Ash's secret passion for the Bee Gees died along with the man himself, while his sex with Martha is now robotic - quite literally textbook intercourse.
The wonderful portrayal of character means that it's easy to forget you're watching science fiction at all - no matter how far-fetched the events of 'Be Right Back' become, you just buy it. Hayley Atwell is particularly sensational in the lead role - the gorgeous Captain America star plays down the glamour to bring sweet, desperate Martha to life.
It's through a combination of Brooker's superb script and Atwell's performance that so many moments - Martha's demented giggling in the mirror or her slamming the door in the police's face rather than confront the truth about Ash's fate - just feel so real.
Domhnall Gleeson has only a brief opportunity to make an impact as the real Ash, but he's immediately endearing, and his performance as the Ash replicant is similar but different enough that the viewer immediately feels a sense of unease, even before it becomes truly apparent how huge the chasm is between man and clone.
Unfortunately 'Be Right Back' does stumble just a little at the final hurdle - after events reach a literal peak on a windswept cliff-top, we're treated to a coda that sees Martha lock her problem away in the attic.
By shutting Ash away, she's copping out of any difficult decision. But this ending also feels a little like a cop-out from Brooker too - like Martha, you get the feeling that he doesn't quite know what to do with Ash now that he's created him.
But that's pretty much my sole niggle with what is otherwise a fantastic production. Probably the biggest compliment you can pay 'Be Right Back' is that Brooker and his excellent cast make the bizarre seem oh-so-believable.
Black Mirror's series two premiere is creepy and moving in equal measure. It has real heart and characters that live and breathe - even when they don't.