I'm Tom Bradby – this is why I wrote my new ITV thriller Secret Service, and why it feels more terrifyingly realistic than ever

This article first appeared in Radio Times magazine.

Once in a while, as a writer, an idea comes along so compelling you burn to head to your laptop and start working on it straightaway. Secret Service, which was a Sunday Times bestseller and is now an ITV drama, was one of those moments.

It was 2017 and the world was spinning a lot faster on its axis: Brexit; Trump; the scandal the US President would come to term the “Russia hoax”, in which he stood accused of effectively being a Moscow Centre sleeper asset; allegations that the Russians had been trying to bribe or blackmail politicians across Europe…

This changing geopolitical environment was occupying my every working moment, as it was most journalists. It seemed to me that several things were obviously true: we were in a new Cold War, which was more complex and more dangerous than the old one, and one in which our enemies’ goals – undermining democratic norms and ultimately democracy itself – were considerably easier to achieve.

After all, there were plenty of Russian oligarchs sending their sons to Eton, and slipping into the milieu of Western elites was proving all too simple. And achieving their aims didn’t require the binary choices of old. If multiple allegations of Russian collusion in America were investigated and found untrue or unproven, the poisonous divisions fuelled by the very accusation itself remained. If we were in a new Cold War, it seemed to me that the Russians were winning.

One sunny afternoon, I was walking past the Secret Intelligence Service’s HQ in Vauxhall, London, when I started to wonder what it would be like for a real-life SIS officer to be wrestling with some of these issues.

What if you were running an operation to bug some Moscow Centre bigwigs on vacation, which yielded the nuclear weapons-grade intelligence that the British Prime Minister had cancer and was about to resign – and that one of the candidates to replace him was some kind of Russian asset or spy? How would your superiors react? What if the Foreign Secretary, technically the boss of SIS, was one of the leading suspects?

Sometimes, an idea leads swiftly to characters and a storyline, but never (for me) so rapidly as in this case. Before I’d reached Westminster, I had an outline of the plot and a pretty clear idea of my lead character, Kate Henderson. I wanted her to be morally and physically courageous but a woman juggling teenage children and a happy family life with a job that makes enormous psychological, intellectual and sometimes physical demands.

Earlier on in my career for ITV News, I had been a foreign correspondent based in Asia. I had periodically been deployed to dangerous places, so I know what it’s like to have a young family and feel incredibly conflicted and uncertain about getting on a plane to a war zone.

I also know what it feels like to be shot (Jakarta, 1999, in a riot). I wanted to bring all of that to the way I painted Kate. Courage in her world must inevitably come at a cost, both physical and emotional.

I wrote the novel faster than any other (I have just published my 11th) and what I do find curious when I look back at the speed with which Secret Service poured out of me is that it seems obvious that Kate – as a result of all the pressure heaped upon her – is skating on the edge of acute insomnia and some kind of breakdown. And shortly after I finished it, this is exactly what happened to me.

I took three months off, rebooted and recovered. But when I read the book now, I do wonder at the way the character was a direct reflection of my own psychological state of mind.

That afternoon in Vauxhall, I originally conceived the story as a TV drama. Ever since I turned my first novel, Shadow Dancer, into a film (directed by Oscar-winner James Marsh and starring Andrea Riseborough, Clive Owen and Gillian Anderson), I had done a lot of screenwriting for various producers. I pitched the idea of Secret Service to a few of them, who were enthusiastic. But in the very act of pitching, I realised the idea was so clear in my head that I couldn’t wait around for the TV development process to unfold in order to write it.

The novel did gratifyingly well, climbing to near the top of the Sunday Times bestseller list in paperback. And as soon as it was done, I started work on the television drama I had always conceived.

I decided by then that I wanted to turn each of my novels into a film or TV drama myself in partnership with Gail Egan (The Constant Gardener, A Most Wanted Man – among many other films), a brilliant producer I particularly rated and liked. She found me a great co-writer called Jemma Kennedy to share the load on Secret Service and we pitched the idea to head of drama Polly Hill at ITV, who loved it. So very quickly, we were up and running.

We worried immediately about topicality. By the time this came out, would it feel like yesterday’s story? We needn’t have been concerned. The strangest aspect of the whole thing has been the terrifying way it has felt more realistic with each passing day.

As I write this, a Times headline suggests European leaders think an unreliable US is no longer the worst-case scenario the continent and Nato faced. That was reserved for the possibility the US might actively turn against us and forge an alliance with Russia. I mean, what the hell is happening to our world?

Polly was good at keeping me on point with the politics. Between the novel and the drama, the government changed, so we made one of the leading candidates to become prime minister a new kind of left-wing populist: charismatic and heavily to the left on tax, spend and social policy but right-wing on immigration.

Given that I spent 10 years as ITV’s political editor, it was important to me that the politics felt credible and the leading ministers, played by Mark Stanley and Amaka Okafor (and their special advisers) were viscerally real to me from their very first lines on set.

But then, this whole production was a bit of a magical experience. It’s not always like that and the road to the screen is a mystery tour, with no guarantee you will be fond of the end result.

It helped that James Marsh signed on to direct the first three episodes to mark our second collaboration and that Gemma Arterton agreed to play the all-important lead role. Watching her bring Kate so brilliantly to life must be about the best experience of my working life. Rafe Spall did a fabulous job playing her husband, too. I found their scenes together electrifying.

The aim was to make a really compulsive, high-octane, nerve-shredding but emotionally rich thriller. A spy story, family drama and political thriller all rolled into one. We want people to sit glued to their sofas and preferably stay up half the night to finish it. To succeed, we always knew it must land as a piece of mainstream entertainment. But I’d be doubly thrilled if we could achieve all that and have people chewing its ideas over with friends in the days afterwards.

It’s not hyperbole to say that we live in challenging times and the more we understand the threats, the stronger our democracy will be.

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