Director Mike Leigh is renowned for making movies the hard way, as he tells Alison Jones.

Film maker Mike Leigh is notorious for his lengthy collaborations with actors.

Script and characters are literally a blank page at the start of the story-telling process, the words to be thrashed out through improvisation, the backgrounds meticulously researched over many months.

Even regular collaborators, like actor Jim Broadbent, say the experience, though rewarding, is too intense for him to contemplate working on back-to-back projects with Leigh.

What might not be so well known is that Leigh developed his singular method of working while at the Mac back in the mid-60s.

“I went to work in the Midland Arts Centre in Birmingham when it opened in 1965 and had the opportunity to start doing what I’d realised was what I wanted to experiment with – that writing and rehearsal could potentially be part of the same process,” explains Leigh.

“If I wrote scripts conventionally I’d sit in a room with a pen and paper or a word processor and I’d improvise onto it, then I would put order to it, then I would get actors to do it.

“I shift the whole process so I collaborate with the actors and create an environment in which they, once we have created the characters, then improvise and we explore situations and bring into existence the whole of the film.

“The journey of making the film is the journey of discovery as to what the film is.”

It means that, when they sign up for a Mike Leigh movie, his stars know next-to-nothing about it. Not the dialogue, not the plot structure, nor where their character fits into the grand scheme of things.

It is an approach that demands they place a great deal of trust in their director.

But with a back catalogue that includes such acclaimed films as Secrets and Lies, Vera Drake, Life is Sweet, Topsy-Turvy, Naked and Happy Go Lucky, as well as the Plays for Today series that includes Nuts in May and the near iconic Abigail’s Party, it is trust that is usually amply rewarded.

“They know that, broadly speaking, I know what I am doing or, if I don’t, own up to it. It is a mutual thing.

‘‘We go on this shared adventure together and it is very, very dangerous. It is a serious, dangerous, confronting, thorough experience.

“That being the case it is a very rich experience for everybody.”

He allows himself and his cast the luxury of an extraordinary amount of time to work on the project before the cameras even start rolling.

He acknowledges it is not a method that would sit well in Hollywood where he describes film-making as “an industrial process where everything is predetermined and pre-packaged”.

However, he feels it is far more rooted in the tradition of performance and, indeed, cinema.

“Long before anybody ever wrote down the script of a play, people were making drama in the way that I do.

“It is how films were made universally before the talkies came in. In the days of silent cinema people went out and created stuff. They got up every day and said ‘what shall we make up today?’ basically.”

His latest film, Another Year, is a meander through 12 months in the company of a happily married couple on the cusp between middle and old age.

Tom (Jim Broadbent) is a geologist and his wife Gerri (Ruth Sheen) a medical counsellor. They are content with their lot and enjoy a good relationship with their community lawyer son, Joe (Oliver Maltman).

Over the year they act as hosts and sympathetic ears to their less fortunate friends – Gerri’s lonely, self-pitying work colleague Mary (Lesley Manville), Tom’s alcoholic and equally lonely old school friend Ken (Peter Wright) and Tom’s taciturn brother Ronnie (David Bradley).

The passing of time is marked in the seasons Tom and Gerri spend tending their allotment. There is a birth, a death and a new relationship is begun.

It has been called the most important film of his career but Leigh, 67, is quick to dismiss such dramatic pronouncements.

“I will only be able to measure that when I have made all the other films I want to make. Then we can sit down and assess the whole thing.

“Having made Happy Go Lucky, which is about youth or youngish people, I thought I needed to do a film which deals with life from the perspective of we who are getting old.”

It is a beautifully observed story of, by and large, unremarkable lives, filled with moments of unexpected laughter and of quiet despair.

Leigh’s acutely observed films are often unfairly dismissed as depressing but he contradicts this, saying they are, in fact, rich in humour “because life is hilarious”.

“I am a professional humorist, I am also a tragedian. I am both things because life is comic and tragic.

“I was in a screening of Another Year with 2,000 people in Leicester Square and people were laughing at all kinds of incredibly dramatic moments.

“In New York they did the same thing but they weren’t the same moments.

“One of the interesting thing about this is a lot of people don’t notice the couple are called Tom and Gerri until about two-thirds of the way through when Katie (Karina Fernandez) laughs at it.”

Although he originally trained as an actor at RADA, Leigh switched swiftly to directing at East 15 Acting School, where he met his ex-wife and frequent early collaborator Alison Steadman.

He made his name writing and directing television films for the Play for Today series in the ’70s and early ’80s, and he reflects back on it as a “golden age”.

“It was a very rich period in the BBC and it was the only way you could make films. There were no indigenous, proper films being made at all.

“Of course one was frustrated because they weren’t feature films but I think, in retrospect, that was misplaced because it was a golden age actually.

“Yes it was restricted (time wise) but only if you measure it against the motion pictures that we have done later. Nuts in May came out of Pebble Mill in Birmingham and was made in 16 days on a very low budget at a time when all technicians were working to rule because of an industrial dispute.

“But it is popular to this day because it has got a rawness and immediacy which was undoubtedly stimulated by the conditions in which we made it.”

* Another Year opens on Friday, November 5