Preview: The Last Enemy, BBC1

The faceless enemy who's watching you

Big Brother is watching you. As portrayed in The Last Enemy, a darkly disturbing new BBC1 serial, we reside in a nation where every time you use your credit card or swipe your Oyster card, a sinister and unaccountable official force is able to track your every move.

The Last Enemy is a fiction, penned by Peter Berry (Prime Suspect 6 and Kiszko – A Life for a Life). The drama is set in a dystopian Britain a few years hence. Spurred by a terrorist outrage at Victoria Station in London, which killed 213 people, the government has cracked down on civil liberties, and there are armed police on every corner.

With more than five million CCTV cameras – one for every 12 people – the UK is already the most spied-upon nation on earth. On average, a British city dweller will be captured on film as many as 300 times a day.

In a key scene during the first episode of the series, the main character Stephen (Benedict Cumberbatch), a science boffin, is invited to comment at Cabinet on the government's proposal to install a top-secret ID system codenamed TIA (Total Information Access).

The viewer follows Stephen's quest as he uses surveillance technology to find out what has happened to his brother Michael (Max Beesley), a charity worker in Afghanistan, and Michael's wife, Yasim (Anamaria Marinca), with whom Stephen has fallen in love. Stephen is tailed by Russell, a security operative brimming with silent menace (Robert Carlyle).

"This piece is pretty damning about surveillance. What's already possible is frightening," says Carlyle. "Did you know that they can store a billion car registration numbers on a microchip the size of a pinhead? What a murky, murky, dark, dark world."

Fiction has travelled down this totalitarian road before. "Nineteen Eighty-Four was a blueprint for what could happen," the actor says with a wry grin. "I'm sure Orwell is lying in his grave smiling and saying to himself: 'I told you all this 60 years ago, but you just weren't listening!'"

'The Last Enemy' starts at 9pm on BBC1 on Sunday