I'm not allowed to go into detail about the solution they found for this, but it's a good one and involves the beautiful Spanish actress Ursula Corberó.

“There are so many pieces like that,” says Redmayne, “whether Bond or Bourne or Kill Evethat before I accept the role I have to think about what makes the difference. And for me the figure has a nice analogue quality, a classic aspect.

“In Edward's portrayal of the Jackal, he exudes a charismatic power, but you never learn anything about him – 10 hours allows for greater insight into the psychology of the characters and their unfailing passion for their work.” What Ronan has tried to do is to do this with to connect with a sense of who he is.

“What I love about Ronan and his writing team is that these two people – Bianca and the Jackal – are completely determined and focused, but anti-heroes in the sense that some of their behavior is consistently questionable. And yet we hope that if we do it right, you'll still be for both.

“It was interesting for me to plan the composition of the character; It starts off being opaque and then gradually you kind of unravel it,” Redmayne adds. “The balancing act that's so successful in the film is that this person does terrible things and yet you're with them and you want them to live.”

But, he adds, his young son (born 2018, one of his two children with wife Hannah Bagshawe) just wants him to play a hero. “My last film was The good nurseand for a while my kids thought that's what I was – a good nurse, and then they found out I was perhaps the greatest serial killer in history. At first my son was pretty excited about this project because he's very interested in the army and military, but now he realizes that I'm a bad guy and says, 'Dad, can you please just play someone good?' “