Forget George Smiley’s cold war machinations and Spectre’s big budget thrills, the BBC’s newest spy drama is less Tinker, Tailor and more Gone Girl – a domestic chiller set in a paranoid world where no one is quite as they seem.

London Spy, which starts next month on BBC2, stars Ben Whishaw as Danny, a drifter whose life is transformed by a chance encounter with the mysterious Alex (Edward Holcroft). They are joined by a cast that includes Jim Broadbent, Charlotte Rampling and Adrian Lester.

The five-part drama is written by Tom Rob Smith, the man behind a series of thrillers including the S talin-era film Child 44, but London Spy is an altogether more contemporary tale.

“I wanted to find a new way to draw on the traditions of the British thriller and yet turn them upside down and take it in a new direction,” the writer said. “It’s almost a domestic spy story.”

Rather than cold war nostalgia, dead drops and double crosses, London Spy makes the most of its setting to tell a very personal tale of love found and then horribly lost.

When Danny meets Alex it is at Vauxhall Bridge, where London clubbers rub shoulders with MI6 mandarins. This is romance in a world filled with secrets and small betrayals. It feels both familiar and worlds apart from standard spy fare.

For Whishaw it was that difference in tone which appealed. “What felt particularly special about London Spy was that the characters didn’t feel like characters I’d seen a hundred times before in a thriller,” he said at a screening of the drama on Wednesday evening.

“They seemed to be recognisable human beings who just happened to be in a spy thriller. [In fact] I don’t see this as a spy story particularly, even though it uses the framework.”

That was partially the intention, said Smith. “To me the show feels very much seeped in all the many great spy stories and shows that I’ve read and watched and loved, but we also have to find new stories,” he said.

“I think people can be unsettling, introductions can be unsettling and I wanted to look at that. This is a drama that concentrates on spy thriller relationships rather than the spy world.”

It is also as much twisted love story as spy drama. Danny and Alex’s relationship, which takes up much of the opening episode, is both romantic and reckless, with neither man seemingly trusting the other enough to tell the truth.

“It’s about two people who are both in different ways lost but who physically find each other,” said Smith, adding that he does not believe viewers will struggle with the central relationship. “A love story is a love story. You either go with it or you don’t and I find it patronising to straight people to say you can’t see yourself in this love story just because it’s not a love story about you.”

“I do not understand all the fuss,” added Whishaw. “I’m infuriated by the idea that characters in stories have to represent all gay people. This isn’t a story about all gay people, it’s about a particular gay person.”

In fact, he argued, the show’s strength comes from the way it combines the small daily habits of domestic life with the sense of a wider conspiracy playing out around Danny and Alex. “It’s a story full of ambiguity and that’s what motors it along,” Whishaw said.

“You don’t know what you’re seeing, what you can trust ... there’s always another side.”

There is a paranoid quality to the drama, Smith agreed: “A whole question of what is real and is this person really the person I knew? It’s a story about intimacy and who you can trust.”