Born Equal, a potent, yet bleak new BBC1 drama about the plight of the homeless, was originally to be titled To Have and Have Not. That sums up the divide that is at the heart of Dominic Savage's film. Boasting an unusually stellar cast for television - movie stars Colin Firth and Robert Carlyle rub shoulders with Emilia Fox, Anne-Marie Duff, David Oyelowo and Julia Davis - Born Equal explores the gulf between rich and poor. Savage's drama homes in on Swiss Cottage. Although the haves and have-nots live next-door to each other in that affluent area of north London, there remains a seemingly unbridgeable gap between them.
In the film, Mark (Firth) is a hedge fund manager who is toasting a million-pound bonus. On the way back from his celebrations, an acrimonious encounter with an aggressive beggar in a subway causes Mark to reassess his life. Assailed by guilt, he begins to realise the emptiness of his all-consuming pursuit of money and wants to put something back into society. So he volunteers to help out at a local homeless hostel.
There, he strikes up an ambiguous relationship with a young teenage runaway, Zoë (Nichola Burley), and he pours his heart out to her: "I looked around at everything I had, and it just seemed emptier and emptier." Troubled by his feelings for Zoë, Mark refuses to tell his heavily pregnant wife Laura (Fox) what he's doing in the evenings and she starts to suspect him of having an affair. Meanwhile, in the same hostel, a tentative romance develops between Robert (Carlyle), a brutalised ex-con, and Michelle (Duff), a young mother fleeing her abusive husband. But the impoverished Robert is becoming increasingly incensed by the ostentatious exhibitions of wealth just around the corner from their hostel. He snarls to Michelle, "I don't like it when people display it, when it's pushed down your throat. That's when it gets annoying." Trying her best to calm her volatile new partner, Michelle ventures: "We're all under the same sky, aren't we?"
Savage, who won Baftas for both When I Was 12 and Nice Girl, has been slaving over a hot editing desk in Soho. Pausing in his labours, he explains that during many months of research and interviews with more than 50 homeless people, he was struck by the strong sense of "us and them" that stalks so many streets of London.
"The issue I really wanted to deal with was the extremes of difference in people's lives," reflects Savage. "In a place like London, those extremes can be experienced within just a few streets. People can be in hugely different worlds but sharing the same space. The film shows huge contrasts between people and how they live, their ideas, what they've got and what they haven't got."
The most remarkable aspect of Born Equal is that it is entirely improvised. Like real-life speech, the dialogue is jagged and jerky, and sentences tail off without warning. This gives the drama an unvarnished and naturalistic quality. The actors never knew in advance in which direction a scene might take them. The director even shot two alternative endings, and only decided which one to use when making the final cut.
Savage, a genial, bald man who is far more cheery than his films, is a former actor who evidently knows how to bring the best out of his cast. Yet he still admits that the process of improvisation "is scary. Even after five films like this [as well as his Bafta-winning work, Savage directed the acclaimed Out of Control and Love + Hate], I still get totally nervous before each one. But my attitude has always been that this approach concentrates the mind. It's good to feel that this could be your last ever film.
"No one else works like this - Mike Leigh locks down his dialogue after months of improv. It's a huge risk - the actors could be totally embarrassing. That's why casting is so important; it's a long and rigorous process. You might find certain stars who are very closed, and you know that with them it could be a hard journey to something that in the end may not work anyway.
"But once you've found the right actors - ones you know will be in tune with the subject matter - they feel liberated and empowered by the experience. Often you feel manipulated if you stick to a script and can't develop themes. You can feel hemmed in on a conventional film. The restrictions on your emotions put a huge burden on you. This, on the other hand, gives the actors the freedom to fly."
What was the experience like for the actors themselves, though? "Absolutely terrifying," exclaims Firth. "Dominic doesn't even rehearse. He just switches on the camera and says: 'Go for it.' It's like jumping into a freezing pool - you just hope you pop up again alive." The actor continues: "I found it particularly challenging because the character of Mark was so far removed from me. I don't react to my wife or the homeless in that way, and I'm certainly not a hedge fund manager.
"In fact, I wouldn't understand what a hedge fund manager does even if you sat me down and explained it to me for an entire lifetime. Anything financial gets actors into a complete terror. I start to suffocate when I see numbers on a screen. It takes me right back to that utter inability to get anywhere with maths O-level."
For her part, Fox found the improvisation exhilarating. "The whole process makes the drama much more alive. People often watch filming and say: 'It's so boring. The actors just say the same lines over and over again.' There is no danger of that happening on a Dominic Savage film. Every take has a real spontaneity about it - and that is reflected in the vividness of the finished drama."
Sometimes the plausibility of it all got to her. The actress recollects that "in one sequence my character doesn't know where her husband is. She has been awake for hours waiting for him to come home. Playing the scene where Mark finally comes home and Laura confronts him felt very real. I absolutely got into character. So as Laura, I had this awful hollow sickness in my stomach because I thought that my worst fears were confirmed, that he was having an affair and that my life would be changed forever.
"I got myself into a real state, to the point where I had no control. That's what Dominic gets out of his actors - that pure emotion. And that, I hope, is what makes his drama so credible."
Despite such traumas, Fox clearly relished the process. "It's such a delight to work like that," she enthuses. "I feel like I've just test-driven a great car. Now I've got a feel for it, I just want another drive. Perhaps I could improvise something during my lunchbreaks on Silent Witness [Fox has a starring role]."
When Born Equal was announced earlier this year, it was slated to be part of the 40th-anniversary celebrations of Cathy Come Home, Ken Loach's pioneering television drama about homelessness. That film is a rare example of TV having a tangible impact on society; the uproar it caused led to the formation of the charity for the homeless, Shelter.
Savage shies away from comparisons between his film and Loach's. "It's not fair to attach Born Equal to the most groundbreaking landmark television drama of all time. I don't want to repeat what Ken Loach said. And I don't want to make an overly polemical film, either. Once you start tying to make overt political points, that's a turn-off. I made this less out of anger, and more out of sympathy."
All the same, do the people involved in Born Equal believe that a film such as theirs can help to change society? "For years now, I've been distressed about our attitude towards the homeless and asylum-seekers," says Firth. "It troubles me greatly because it's so irrational, so deeply misguided and so cruel. So, as a portrait of what some people are up against, Born Equal is really positive. It won't change viewers' opinions overnight, but it manages to humanise the sort of people we might otherwise cross the road to avoid. Next time someone looks at a homeless person with fear and loathing, they might remember a character they liked from this drama. The best films hang around in people's minds for years. You hear people saying: 'That's like a moment in The Godfather or Casablanca.' I'd love this film to seep into people's consciousness in the same way."
Powerful as it is, Born Equal is scarcely uplifting. Light years away from traditional, heartwarming Sunday-night fare, it will not be bringing Christmas cheer to the nation's living rooms. But Savage makes no apology for the challenging nature of his film. "The previewers might say: 'This is dark, gritty, difficult', but people shouldn't be scared of those areas. That's where the most interesting drama lies. It does not reside in 'And they all lived happily ever after'."
'Born Equal' is on Sunday at 9pm on BBC1Reuse content