In The Day of the Jackal, the titular character is a man with many faces – literally.

A professional assassin armed with an array of disguises, skills, weapons and cunning, he has proven impossible to find even by the smartest minds of international intelligence.

Living a double life, no one is aware of the true nature of The Jackal – not even his loved ones. But with the game wearing thin, one last job promises to give him the opportunity to leave the job behind him forever.

But things aren’t always that simple, and with MI6 agent Bianca Pullman hot on his tail, The Jackal needs to keep his wits about him before his entire world collapses.

Ahead of the series launch, Eddie Redmayne talks about taking on the iconic character in this new adaptation of the 1971 Frederick Forsyth novel, how the show gives the story a modern-day twist, and how he assumed his most challenging role yet.

Find out more about Eddie Redmayne here.

The first three scripts arrived, and when I saw the title, it had been a film that I was brought up on. I had read the book a long time ago, but I just adored them both. It was one of those films my family would come back to almost yearly.

I found the idea of that character quite intriguing. I started reading the scripts and they were so compelling and the story was so propulsive. It felt as if it was a genre we recognize yet it felt like it had a unique quality to it. I just wanted to know what was going to happen next. I also thought it would be a challenge from an acting point of view.

The idea of starting out by playing a 65-year-old German cleaner, then moving through several other guises, along with the different languages – French and Spanish – mixed with the shapeshifting, the physicality, and the prosthetics, it was an actor's dream. They're all joyful things to engage with and a massive challenge. You sit there going, “It's going to take quite a lot to convince an audience that I’m a 65-year-old German janitor!”

Although the book and movie are so iconic, this felt inspired by, but equally completely free, from them both. It was a completely different beast. It did however retain an analogue quality, which is what I love about the older versions of this genre.

It's not computers that are doing whizzy things, it's clever contraptions that are handcrafted and built. The Jackal is an artist. He assumes identities and creates these prosthetics himself. He's a sculptor, a mimic, and a linguist.

Therefore in some ways, it feels like he's an actor. What I read genuinely felt like a thrilling story I hadn't seen before, with a character I was curious to play.

As the world becomes increasingly with AI taking over there’s something old school – both an analogue quality but also an elegance – to who this character is.

There’s a certain peacocking about him. He enjoys all the elements of his job. He enjoys the planning, the chess work, and the thinking three-moves-ahead. And there's a great delight when those dominoes are set up and set off.

And then, of course, the second that cascade gets disrupted and it falls apart then it's about watching someone who's used to having such a level of intricacy and control, watching that fumble out of control.

Lashana and I met early on in this process. I adore her. Her instincts are brilliant. What is extraordinary is that I think we were on set together once. It was strange to make something where we were both in our own vacuums, telling our story.

Here are two people who are driven by something, and though their morality seems to be slightly all over the place, there is a focus and a drive there that feels mirrored.

In that sense, they are good matches for each other.

The archetype of the empathy-less assassin whose blood runs cold couldn't work in this version. It is 10 hours long. We have him as a family man with a military background. Is he also sociopathic? That's sort of what I believe.

There's been a juncture in his life from which point he can hold those two things at the same time. He has his own logic of empathy. He had assumed he would be alone all his life. And yet when he meets his wife, Nuria, and is floored by her charisma, it's an Achilles heel.

So when we meet him he's made a huge amount of money, he's married with a child and he wants this to end. He's lied to his wife from the word go but he thinks he can wrap it up if this thing ends, and they can start a new life.

That's his weakness as an assassin. We leaned into their love for each other and his love for his son. That’s important and I hope what slightly differentiates this version of Jackal is you'll believe all of that and care about the outcome.

Through The Theory of Everything and The Danish Girl I worked with this wonderful movement director, Alexandra Reynolds. Here was another moment playing all these different characters, that I could go and work on physicality with her.

We found a rehearsal room at the London Dance Academy, just for a few weeks, and we played with the idea of not only who the Jackal was.

She found this quite brilliant video of David Bowie being interviewed in the ‘70s or ‘80s that I found inspiring. It's one of the only times he's being interviewed as himself and the interviewer is talking about his physicality and identity and putting on different costumes.

It was interesting not only in his capacity to listen and his inscrutability but also in his talking about these different personas.

I don’t speak a word of German or Spanish, so that was a hilarious challenge. Fortunately, I speak a little French, so that was a touch easier.

I had a wonderful dialect coach – a German woman, Simone – and we worked for months on end. You're learning it not only phonetically, but musically.

Simone would have to not only translate the words but the way I wanted to say them, the cadences.

I ended up with thousands of these voice notes. I’d get it sounding alright but then once I had the prosthetic on, doing it in my voice in German looked ridiculous, playing this old chain smoker. Therefore it became about trying to throw my voice to this weird place that looked completely ridiculous when you’d say it yourself, but when you see it, it works.

This feels big. The scope and the locations, the glory and indulgence of seeing beautiful parts of the world, and the globetrotting-ness feel fully realised.

What I loved about the original movie was that from our living rooms, we got to leap across the world with someone who seems to nip on a train or a plane as he pleases. I hope audiences enjoy going on that ride.