James Nesbitt plays Tom Jackman and Mr Hyde
Steven Moffat had absolutely no doubt about who he wanted to see in the lead role of Jekyll, someone who could really get under the skin of this dual personality.
"I don't know what slinks around the dark side of James Nesbitt's mind, but right at this moment I'm guessing he thrashes in his sleep every night, muttering 'Michael Caine, John Barrymore, Spencer Bloody Tracy!'
"Because this is not just one of the all-time greatest parts ever created for any actor breathing, it's two of them. And it's not just been played by some of the best actors ever, it's been played by a whole damn list!"
So how did they go about casting this incredibly challenging role?
"Well, we made one of those lists. You list every single actor you can think of with a huge BBC One following, the acting chops to pull off a famously impossible part, enough charm to beguile you as Hyde even as he terrifies you, enough darkness to keep you on edge as Jekyll even as he breaks your heart ... and then you look at that list and realise that if James Nesbitt says no, you're clean out of ideas."
But he said yes: "Thank God! Not that we didn't try to put him off. No big make up job, we said – no hair, no fangs. It's got to be all performance! You've got to be two people, completely different in every respect – and the amount of help we're giving you is practically none.
"James took the challenge like a man; he nodded soberly, asked endless annoyingly intelligent questions, and turned an ever more spectacular shade of green as filming approached. And what can I tell you? Over the next few months he turned in one of the most astonishing, inventive, heartfelt and daring performances I have ever seen."
James takes up the story: "I first met Beryl Vertue at the Comedy Awards and I remember the occasion well because we really clicked. Over the years, we continued to meet up and we always talked about working together.
"Then, about a year ago, Jekyll came up as a possible project for us, and she sent me Steven's scripts. The title immediately grabbed me and the writing was incredible: shocking, funny, dark – and I didn't hesitate – I was desperate to do it!"
He continues: "There was a real buzz about the drama in the industry and it has been very exciting to see it take shape. I had plenty of time to read the scripts and the drama was always there in the back of my mind so I found myself observing and absorbing all the time.
"I also read Stevenson's book a couple of times and I watched a number of films which have somehow stayed in the album of my memory: Star Man with Jeff Bridges, the alien who comes to Earth. Some of his physicality was useful for Hyde. And Natural Born Killers.
"I also found that I could use pieces of myself that probably haven't been allowed to surface since I was a little boy and my mum told me to stop showing off, which has been incredibly liberating, very therapeutic!"
Jimmy was determined to enjoy the whole, albeit challenging, experience: "Actors get this sort of opportunity very rarely and it's a very precious thing to have been given. I'm surrounded by a brilliant cast and our producer Elaine and Beryl and everyone at Hartswood Films have been unbelievably supportive; Beryl always stressed how important it is to have fun when you're working so hard."
The biggest challenge, of course, is that Jimmy plays two roles, which he relished: "My on-screen exposure over the last few years has been quite high, so I wanted to view Jekyll as a blank canvas from an acting point of view. It would be very easy to sit there and say: 'Well, everyone has a dark side,' but I think that is too simple.
"As much as we want to lead good, decent and happy lives, I think we're also attracted by something that may lurk within ourselves and the people around us. I play Jackman and Hyde as two very different characters who had to be totally different in the way they behave."
The flamboyant, self confident, posturing Hyde seems at first to be the biggest acting challenge: "One of the most important things is to make the fantastical believable. Hyde is very confident and grand-standing, larger than life, and that was a bit scary at first, a bit like diving off a board really.
"He is also very single minded. He has no fear or moral conscience, no social or moral responsibility. He wants to eat, drink, shag, dominate and just be. And he's a child. We meet him moments after his birth. He's a show-off, and being given an opportunity like that is probably what most actors crave! And to show off very good writing is great.
"But I was very wary of lapsing into Jim Carrey mode. There is always that fear that the crew will look at you in that way the producers do when they first hear 'Spring Time For Hitler' and they cut to the audience and they're all slack-jawed. But once I had the confidence backed up by the writing, it was a fabulous experience."
And, of course, it's always fun to play someone with super powers: "Hyde can do the lot; as the story progresses we find out how amazing he really is. What I like about him, apart from his extreme unnatural superhuman powers, is his fearlessness. And the fact that he's only just been born in many respects means he's quite childish, petulant and easily bored.
"But it was also important to ensure it wasn't about funny voices and movements. The character had to be credible. Modern evil is seductive and brash and cool, and still capable of extreme violence. Hyde is not a fanged and monstrous character but more attractive and seductive.
"He has a constant swagger, that ability to move wherever he wants and take everything as it comes. Whereas Tom deteriorates emotionally and psychologically and he has to muster up as much inner strength as he can."
He adds: "I didn't want Hyde to have just one rasping, purring, sexy kind of voice, so we played around a lot with that which really helped; at any given time he can adapt and use voices but without it looking as though it's been thought out."
It soon became clear to Jimmy that playing the repressed, increasingly isolated Jackman had its challenges too: "Hyde is such a huge character that you can have a lot of fun with him, but Jackman is more human, which is always harder to play, as you have to find his pain. In many ways he became more difficult to play because of his journey.
"You're creating a more complex individual, someone who has had to move away from his family, who is trying to suppress and contain this 'thing', this evil character who is taking him over, who has to live with the knowledge, is totally isolated and has noone to turn to. The human cost of having to retreat was probably toughest of all to play.
"What's attractive about Tom is that he doesn't have the sleek, overpowering nature which is attractive in Hyde, but he does have an inner resolution and a stoicism that is admirable and he doesn't give up the fight."
He continues: "With Jackman you also get to develop relationships, with his wife Claire and with his assistant Katherine, which makes playing him feel more collaborative. Hyde doesn't really care about the other characters! But then there are moments that even Hyde finds surprising, where human emotion is beginning to leak into him, where perhaps he's developing his own sense of human feeling."
Whilst performance was key in the differentiation between Jackman and Hyde, the physical transformation is very subtle, as Jimmy explains: "I went in for a lot of make up tests. Ultimately we want the audience and the characters who work around Hyde to almost do a double take, to think: 'What's the difference? Is something not quite the same?
"The eyes are a different colour – it's amazing how simple an effect like black contact lenses can be, not just from a visual point of view, but also in terms of character, simple but shocking – there's a very slight elongation of the nose, a protrusion of the chin which makes the face more angled, a subtle difference in the ears and a bit of a difference in weight – and it's great that I finally get to wear wigs!
"I've been saying to make-up artists for years that I want a fully head of curly black hair and now I've got it!"
He laughs: "It's not often that you get the chance to have a face you really want; in the past I've said that it's very depressing to hand over the wigs at the end of the day, but now I also have to hand over my chin, nose and ears!"
The Hyde make-up and prosthetics took about an hour to apply and half an hour to remove: "We got it down to a fine art. I'm someone who's dreadful in make-up.
"I have three older sisters who, when we were children, used to hold me down on a bad day and put make-up all over me, so I've had an aversion to it all my life and hate sitting down in the make-up chair. So, at first, this was torture for me, but Irene, the make-up designer, made it all as painless as she could!"
He adds: "I've also been blessed with two fantastic directors on this, Douglas Mackinnon and Matt Lipsey – our collaboration was key. The deterioration of Tom as Hyde gains more strength is very important to chart and chart properly and they really helped me keep tabs on that."
The series was shot on location in and around London, from the East End to stately homes, some of which were falling into disrepair: "The scenes we shot in a private zoo were extraordinary. The animals are all in incredible nick.
"And what a great scene to do, the contrast of the father Tom seeing his small son in the cage with the lions and what that must do to you as a father, and then Hyde arriving, thinking 'this is great!' and just having a ball!"
As for whether he identifies with the characters, Jimmy laughs: "My wife would say I'm more Hyde than Jekyll! Some actors can distance themselves from the parts they play, but I fall into the category who use bits of themselves.
"To tell you the truth, I identify with Tom's love for his family, being away a lot of the time. But there are certain elements of me in Hyde as well. Even though Hyde is what we see as the modern personification of evil, there's an intelligence about his humour that I love – he's smart, and I think that's attractive.
"There are elements of Hyde that I would love to have in my life; you'd never dare to talk to people in the way he does or move in that way or even think you could possibly get away with some of the stuff that Hyde does – he reads people and situations brilliantly, and I love that."
He concludes: "This is a classic tale that people have been transfixed by for 100 years because they are fascinated by the idea of the alter ego, the suppressed dark side.
"Jekyll is epic in its scale but of course there is a very human story here as well and it's quite terrifying; about a man who is totally isolated, living away from his family, with a terrible dark secret.
"This leads to an incredible amount of tragedy and human pain and it's a question of finding a balance. The drama will only succeed if the audience believes in the characters and has empathy with them, and I think Steven has done that with his writing and although this is an ambitious, crazy project it is fundamentally a human story about love and loss.
"I've loved it. It's been a terrifying but incredible journey. It's also been hard work – absolutely shattering. Fourteen weeks of playing two parts. But I'm not complaining as I have had the opportunity that any actor would kill for.
"I can't stress enough how much I have enjoyed working with Beryl and Hartswood, and with Denis, Michelle, Gina, Meera and all the cast. We've all really enjoyed it too – it's a great project with great people and I can't imagine a world in which I wouldn't want to do another series."