Mike Leigh - Secrets and Leigh lines

It's the middle of the London Film Festival, and Mike Leigh is sitting two rows in front of me at a screening of The Arbor. As much as he might be interested in Clio Barnard's film about the playwright Andrea Dunbar, you can bet he's also on a fact-finding mission.

After all, with a crop of virtual unknowns in the cast, the film is a goldmine of untapped talent for Leigh to get his hands on. Such diligence is what it takes for the venerable British director to keep fresh blood flowing into his ever-expanding repertoire of actors. Indeed, there's a strong argument to be made that the 67-year-old is the greatest actor's director British cinema has ever known.

His record speaks for itself. David Thewlis won Best Actor in Cannes for his nihilistic loner in Naked, while Sally Hawkins won a Golden Globe and a Silver Bear in Berlin for her work as the upbeat Poppy in Happy-Go-Lucky – two characters that couldn't be further apart. Imelda Staunton won a Bafta for her lead in Vera Drake and Jim Broadbent won the Volpi Cup in Venice for W S Gilbert in Topsy-Turvy. Before this, Brenda Blethyn won Best Actress in Cannes, a Golden Globe and a Bafta for Secrets & Lies, while Ruth Sheen claimed Best Actress at the European Film Awards for the left-wing wife she played in High Hopes.

Of the last 10 features Leigh has made, six have claimed major acting awards – an astounding record by any reckoning. And consider the actors he's worked with at the outset of their careers, such as Tim Roth and Gary Oldman (council-estate lads in 1983's Meantime) or Jane Horrocks as the bulimic daughter in Life Is Sweet. More recently, Andy Serkis, Gollum in T he Lord of the Rings, played a yuppie in Career Girls and James Corden – "who wasn't as famous or notorious as he is now," says Leigh – played the overweight son in All or Nothing.

Leigh's latest film, Another Year, offers, as he puts it, "the highest percentage of people I've worked with before". "It's like a greatest hits collection, isn't it?" laughs the actor Martin Savage, now on his fourth outing with Leigh. He offers an explosive turn in the film as Carl, nephew to the central figures of Tom and Gerri (Jim Broadbent and Ruth Sheen), a content north London couple whose lives and friends we observe over four seasons of one year. Indeed, aside from the six "Leigh regulars" we talk to about working with him (see over), you'll also find Imelda Staunton, returning for her second Leigh experience, after Vera Drake, with a blistering performance as a woman suffering from depression.

The same goes for Peter Wight, so memorable as a security guard in Naked and a detective inspector in Vera Drake. His turn as Ken, Tom's old friend, is heartbreaking, full of fear and desperation. "Peter Wight is an incredibly emotional, sympathetic, profound kind of actor," says Leigh. "He's a philosophical guy, and he brings that implicitly to the performance. He's great – but they're all great. If they weren't great, I'd get rid of them!" Leigh works with character actors, not stars with screen baggage: "They don't present their egos."

Partly, there is a practical reason for Another Year being full of Leigh regulars. He needed actors who were already au fait with his methods. "We got the greenlight to make the film and we had to get on with it very quickly," Leigh says. "Normally, I have a long period of auditions. Now, I could've worked with people I haven't worked with before who I'd already auditioned. But it felt like a good opportunity to pull in people who I knew were reliable. So we got down to it quicker than we normally do."

Always beginning a new project without a script, Leigh is famed for his unique form of improvisation. He works one-to-one with actors over a six-month period to build characters from the ground up. For Another Year, Broadbent began by giving Leigh character sketches of "over a hundred men I know" before whittling it down to three individuals. "We use those three as a seed to build up an organic character and then invent this back-story and where he lives, who his siblings are, and bringing it all together."

At this point, actors are "introduced" to other actors in the cast, in the order their characters would meet in life. Broadbent first worked with David Bradley, who plays Ronnie, Tom's elder brother. Then came Peter Wight, followed by Ruth Sheen and finally Oliver Maltman, who plays their son, Joe. "It's very chronological, as is the filming," says Broadbent. All the while, of course, Leigh hones the story in his head, using the characters he and his cast have developed.

Inevitably, it's not a process for everybody. Some actors often feel nonplussed by the fact that their character can be relegated to a bit-player (as with Serkis, who spent months hanging out with stockbrokers only to be left with little more than a cameo). Then there's the danger of immersing yourself in a character for so long. As Gina McKee recalls of her time playing a waitress in Naked who crosses paths with Thewlis's character, "I went to a dinner party and one of my friends asked, 'Do you not bring it home with you?' I said, 'no' and, at exactly the same time, my husband said 'yes'."

Even for those who enjoy the process, it's exhausting. As Lesley Manville – who plays Another Year's Mary, a middle-aged singleton with a drinking problem – says, "You couldn't do back-to-back Mike Leigh films." But she's Leigh's most frequent collaborator, having worked with him on television, radio and film. Theirs is an "on-going exploration", according to Leigh, which gets richer at every turn. Like many of Leigh's well-known stars, she'll happily come in for a day to play a bit-part for him, as in Secrets & Lies, where she played a social worker.

"The important thing about working with an actor I've worked with previously, [is that] we make a strict commitment that whatever we do, we won't repeat what we've done before," Leigh notes. "We'll go into another area." You wonder where he will go next with the younger stars of Another Year, such as Savage, Maltman and Karina Fernandez, who played the flamenco teacher in Happy-Go-Lucky and here returns as Joe's girlfriend, Katie. Along with Helen Coker (All or Nothing, Vera Drake) and Sally Hawkins, they are the next generation in Leigh's remarkable troupe of actors.

Stars reveal demands involved: 'It's full on all the time. You have to be on the ball...'

Jim Broadbent

Leigh Collaborations: 7

Before you take a project with Mike, you've got to really think it through very carefully. Having been doing it with him for 30 years, you know what it entails. You don't just drop everything. I was fairly sure I would have quite a good part on Another Year, that I wouldn't be sidelined. But I knew it was going to take quite a long time, and I didn't know what the part would be. It was clear it wasn't going to be a project like Topsy-Turvy, where Mike knew what it was going to be about, and he could share that with me at an early stage. The experience varies quite a bit. Thirty years ago, the novelty meant it was a big, exciting thing. You think, "What an extraordinary way to work." And later on, you know all that, so you don't have that novelty. You know how he's going to do things. And actually there are long stretches of the process that are quite time-consuming and quite tedious, when you've done it lots of times – though necessary. But you do have to get through them. You're involved in every aspect of what's in front of the camera, particularly if you're playing a central character. You're part of the design. You decide what car he drives. You decide what the kitchen would look like, what the décor in the house would look like.

Martin Savage

Leigh Collaborations: 4

Mike can be scary. But you've got to be well briefed, and if you're not, then woe betide you. I learnt very, very early on, on Topsy-Turvy, if you don't have something witty or pertinent to say, then it's probably best to say nowt. You must make sure your contribution is worth something. And that's not necessarily intimidating, it's about quality control and trying to get the best out of people. And that's certainly what he's about – trying to make the finest piece of work he can. And that makes you want to do the same thing. But it doesn't suit everyone and I think Mike would be the first to admit that. Some people he's worked with, they don't like the fact that they don't know what's coming. Or they may not be comfortable playing characters. A lot of actors do want to play themselves. So when he's asking them to develop a character that's a long way away from them, I think some of them struggle. And without putting too fine a point on it, I think some actors struggle to improvise. Being alive and spontaneous and in the moment, in character but without an end in mind... I think a lot of actors think, "We've got to make this scene funny." Which is not how improvising with Mike works. We're not trying to be funny!

Ruth Sheen

Leigh Collaborations: 5

Another Year was the most exhausting film I've done with Mike. It really was. I wasn't sure if it was because I was older, and found it more difficult, but to be in the film all the time, at all the rehearsals and all the filming, it's unrelenting. You're always creating. You're rehearsing in the morning. You're working out the scenes, shooting them in the afternoon, and you've never got a script. It's quite full on all the time. And you've got to be there. You can't phone it in or be half-asleep. You have to be on the ball all the time. We only meet up in character. And we only talk about it with Mike. You're not allowed to chat about your characters while you're sitting having your lunch. You have to talk about something else. It's very disciplined in that way. In terms of what we get paid, I think basically it's very low, across the board. It's very basic. No one has a Winnebago. We all have lunch together, just sitting round the table. And Mike treats everyone the same – if your part is tiny or big, or whether you're a big star or small, which is a blessing.

Karina Fernandez

Leigh Collaborations: 2

Working with Mike must be a bit like being a spy. You're set all these tasks and a lot of research, and basically re-inventing yourself, in a short period of time, in a really complete way. But you don't really know what it is you're a part of. My first experience with him was quite unusual. When we rehearsed Happy-Go-Lucky, I was playing another character. She was all finished and "introduced" to a few other characters. But she was so deeply dislikeable that Mike couldn't think of a way to get her into the film. So I was recycled halfway through the process. He called me up and said, "How's your dancing?" I didn't know how to answer. I hadn't really done any dancing, to speak of. Then he called me in the next day. He'd had a brain wave, and doesn't normally start with the end process, but asked, "Would you be up for starting again with the end point being a dance teacher?" He said he hadn't done that before. I think I was trying to second guess the outcome, wondering if I would be in it, how I would be in it, how much I would be in it – and not just letting him get on with it. I do ask a lot of questions wherever I am, and it's not something he appreciates – unless it's questions about your character.

Oliver Maltman

Leigh Collaborations: 2

Once you sign up for a film with Mike, you have to accept that you won't necessarily be playing a substantial part. You just don't know. I think it was Eddie Marsan in Happy-Go-Lucky who thought that the film was going to be about him. I suppose it's the Mike Leigh lottery, which leaves you wishing you had more to do or not. Nevertheless, it's still gratifying. You are actually getting to put that amount of work into something – despite the fact it might not appear as much on screen, you still feel you've got a full-rounded character there. Once you're in the filming process, it's not that everybody walks around in character when the cameras aren't rolling. You come out of character and you leave that to one side. Generally, what's going on most of the time is that you're working on the scene that's approaching. So there's very little down time where you're left to sit and wait. And I think because he puts himself under so much pressure, inevitably he can get grumpy and in a mood during the shoot. But you have to consider what it is he's got on his shoulders. Now he's in his mid-Sixties. He looked very tired at times – though he has so much energy, it's incredible.

Lesley Manville

Leigh Collaborations: 8

I know Mike pretty well and I think on Another Year he probably just wanted to nest himself in the bosom of people that generally he could talk shorthand too, and make a film with all his old-timers.

I don't know if that was partly fuelled by the fact that this is his lowest budget ever. So he had to think, "This can't go wrong."

Over the years, Mike's process hasn't changed really at all. I think a lot of people think it's a very complex and mysterious process, but it is really quite straightforward. You create a character, from scratch. You build up their lives.

You fill in all the gaps. And you start interacting with other characters that would be in their lives. It's quite straightforward, and that hasn't changed.

While I'm very fond of Another Year, I'm also very fond of All or Nothing, which was released in 2002. It makes me cry every time I see it. It touches something very deep in me, and I think that's probably to do with the trauma that happens with her son [played by James Corden] and his heart attack. I suppose the reason that that touches me is because I have a son.

It just gets me every time. But also it's kind of the film that got away. I know Mike thinks that as well. The reviews were very good, but the critics pretty unanimously said, "It's incredibly depressing" and I think that turned people off.

'Another Year' opens on 5 November