This is an intriguing story - how did you get to make it?
Grazer: "Actually it's rather simple, Russell was attached to the film several years before we had all gotten together to make the film A Beautiful Mind. That movie, as we were shooting it was going along rather well even before it's result we were all getting along and he said 'maybe you guys would like to take a look at this script'. Just in that low key way.
"Ron and I read it and fell in love with it, we fell in love with the theme of the movie. We'd actually heard that Renee was interested in it. Or had interest in it, and that if we reached out she would say yes to us. That was a huge attraction to Ron and myself. That's a synthesis of how it all came together.
Renee, was there a lot of research for role?
Zellweger: "Sure, there was a lot of research, I mean so much material. We were spoiled in that respect. One of the actors in the film, Rosemary DeWitt, is actually the grandchild of the Braddocks. She brought so many beautiful pieces of intimate material that we wouldn't have been privy to otherwise.
"And Ron, he just has a particular fascination with this period in American history so there's not much about it that he doesn't know, that doesn't fascinate him or he doesn't find interesting. To walk into their offices in Toronto was to walk into a library about that period in the United States .
"I mean, on the walls, everywhere, were images that I'd never seen before. Compilations of first hand accounts of what it was like to live there at the time, film footage, newsreels, radio interviews and of course the personal effects of the Braddocks everywhere.
"I was spoiled rotten, because I walked in where you usually finish on a film in terms of collecting research materials. So I was like a kid with candy everywhere, in terms of researching this role. We had her voice on tape and film footage of every single blow of each fight that Jim Braddock took part in. There was very little artistic licence exercised in this film, we tried to be as accurate as we could, and it wasn't so difficult with what these guys had compiled.
Grazer: "That's a very modest response. The truth is we had a lot of research and film archives that the actors and the actress, in this case the star, were able to study. What Renee was able to do was to fully inhabit every part of the physics of this character, and the period, and she just did it in a seamless way.
Zellweger: "That's kind, it was fun. She's a neat lady, she was such an elegant woman and had such strength of character to be facing such adversity and to manage to maintain her composure for the sake of the greater good of the family. I just admired her so much the more that I came to know her. She had this impish kind of joy that was just beneath the surface. But she was very elegant and reserved.
"It was different, it was interesting because there wasn't much outward expression in terms of doing this characterisation except that she was very ladylike and of course she had to be of the period and all that, in terms of her mannerisms, but it was quiet. It was different, it was a very introverted sort of characterisation. Different than something that I had done before, but I just found her fascinating.
"Sort of like Anne Lindbergh, I always relate it to Anne Morrow Lindbergh, where to dig beneath the surface in what she had to contribute means to come to respect her a lot. I had the same experience with coming to know Mae Braddock.
Can you tell us about Russell's performance?
Grazer: "Well, he was very dedicated to wanting to make it. I don't know how many years he'd been in love with this character and the subject. And I guess he probably sees, in some version, of a lot of himself in this man Jim Braddock. He was uniquely committed emotionally and physically.
"Ron and I were kind of nervous, because he'd really done so much physical and mental homework on the character in terms of boxing and mannerisms and intonation. Within the final week when he was all ready to leave Angelo Dundee in Australia to come to Toronto to shoot the film he'd injured himself.
"We thought he'd physically never be able to repair himself and we'd all just have to go home. I've been injured many times, all men who play sport get injured, and you just wonder whether you can actually work that shoulder or wrist or arm, and it's scary. So we thought maybe this was just the end.
"And we also thought if it wasn't the end and he comes here and does the boxing it's highly likely he will re-injure himself. And if that happens the movie ends, or we lose Renee because she'd have to go and do something else, issues like that. But we got very lucky.
"His commitment and dedication and love of the character somehow, that passion oddly enough conformed to the passion of Jim Braddock in its period. We finished the film, and it's a film we're all extremely proud of. We're all very dedicated to the movie.
Would you say that Russell raises the bar for everyone, demands more of them?
Grazer: "It's funny, my mind goes to this behind the scenes documentary he did because he loved the movie so much. He just did everything he could possibly do. I saw part of this documentary about three weeks ago, there was 30 minutes to watch. I thought all actors should watch this thing. I don't know how many actors there are, or people that want to be actors, but I think people think it's easy. And it's just so far from being easy to be a great actor or a great actress.
"It's just like the furthest thing from being easy. You do have to do so much studying and research and any of the great ones do that. They don't just wake up in the morning, go to the set and all of a sudden Raging Bull happens. None of that stuff just happens, it's not a mistake. He was very dedicated to it, and every part of him was dedicated and tightly involved in this.
Renee can you tell us about Russell's influence?
Zellweger: "I appreciate it, I understand it, I love to be around it. I don't want to say that I expect it, but it's your job and I admire it when somebody recognises the importance of what goes into it because ultimately I think you see it. I love movies, and I feel the difference when I sit in the audience, you feel the difference. Hopefully not during the film but when you walk away it resonates in some way, and it just elevates the experience completely.
"And when you are carrying a film like Russell did this one it sets the precedent, and yes you do rise to the occasion. And yes it does make a difference, it changes the tone on the set because people know that they're part of something that matters to this person. Like Rob Marshall on Chicago for example, he didn't sleep, it's like he was making four films at once, so how are you not going to do everything that you possibly can to make a contribution? It was the same with Russell and his passion for this.
"He really did become a boxer, his body changed, he changed his lifestyle to discipline himself in that way. He would run to work, he would ride his bike to work, whatever it took because this mattered to him. Responsibly retelling this story of this man that so many people admired was his goal and his passion, and it was infectious.
"As an actor, when you go to work, and you sit in the scene in the room and you're working with everyone cooperatively, the least you hope for is that you tell that bit of the story, you moved it along today, that's what you've achieved and you've kind of done your job.
"Every now and then, it's rare and it sounds really weird, but the experience transcends whatever's going on in the room and what it is that you're animating, or re-animating at the time becomes the reality. And it is extraordinary.
"And that happened a lot with Russell because he's there , so you want to go and join him in that place. It's like the writer who disappears and doesn't realise that the sun's gone down outside and that he's been sitting there with his pen in his hand for 12 hours. It's that, it's when that focus doesn't break and the creativity just flows.
"And Ron [Howard] was the same. His enthusiasm, and his childlike appreciation for what it is that he gets to do is also infectious. And when you go to work with a person who has that attitude about it and is completely without malice, he is an ego free, guileless person, and it doesn't change.
"We made jokes all the time that we couldn't wait to go out into the world and say 'that jerk Ron Howard' because people would just laugh, because his kindness is legendary. It's the truth. That also raises the bar.
Would you say Mae's vulnerability parallels your own experience of meeting the press?
Zellweger: "Oh, absolutely. I have more practice, I'm better at faking comfort. She's terrible at it, she hated it, she was so uncomfortable, she felt very self conscious about it. It's really funny because she had been asked to contribute a number of articles to different periodicals as the wife of this man that everyone admired so much.
"And they were all written differently. I would read the writing style, and the voice would change. I was wondering just how much of that she had actually participated in. It was very interesting, she was completely uncomfortable with her public responsibilities. But there was no question that she was going to be there with him - with the exception of the fights of course, which made her sick.
Are you a boxing fan yourself?
Grazer: "I've become a boxing fan, but I didn't really know very much about boxing, it's not a culture that I was able to particlise and really know how it worked. But by being around the professional boxers, that were trainers and of course being around Angelo Dundee [trainer to Muhammad Ali and Sugar Ray Leonard among others] I got to learn some of the tricks, and I got to learn why the stakes are so high.
"That - when it's pure - it is probably the only sport that is one on one, and there is nothing you can really fake. But the human dimension of course is transcendent of the boxing itself. The boxing is great and it's probably more than atmospheric but it's the human story that is the story that reaches you emotionally. It's not the punching.
"The thing that always made me cry was that for Mae, Renee's character, there was a secret she kept, she kind of knows that Jim is fighting guys who are better than him. And that he might not be that good, but she's never going to say it. She's just going to keep it inside of her, and she'll support him.
"Even though she might believe that he can't make it. He wants it that badly, and they both want it for their family, and that's I think the heartbeat of the movie. Everything comes under this emotional umbrella. And oddly enough, way in retrospect, I realised that this is a similar architecture to a film that we'd made before, Apollo 13, where the human story was so powerful.
"I didn't know anything about mission control, or aerodynamics or anything but it was a subculture that I became interested in. I also became very interested and compelled by the subculture of boxing, and I learned about that. But really the stakes are all in the human beings and the cutting away to Mae and kind of going 'these are the stakes, this is what I care about, it's their lives that are at stake'. I think that summarises it.
Could you do what Mae does as a boxer's wife - could you go to a fight?
Zellweger: "I don't know, I really don't. I'm not sure. I guess it's something I couldn't really speculate about because I don't know what my feelings would be. I would hope so. I would try if he wanted me to be there, absolutely. But to be filmed running away, be talked about running away, then maybe not.
Can you tell us about the historical authenticity of the film?
Grazer: "There's the inherent pressure to always hype things. In Hollywood that's a reflex almost. But collectively, whether it's Ron or Renee or Russell or myself, we've resisted that temptation because we've singularly succeeded at that before.
"On Apollo 13 we said 'let's not have these aerospace guys go into bars and slap each other's asses and drink shots of tequila', because they don't really do that. That's a movie invention. So in this movie we were pretty confident, all of us, to just follow the exact play by play drama of their life and to not manufacture any moments that weren't real.
"So I think we'd all had training prior to making this film to resist that temptation. In fact we'd had many boxing diagnosticians, including Norman Mailer, go over those fights with us and go over the life of Mae and Jim Braddock, and give us exactly the truth so that we could in fact connect those corresponding dots.
Was there any bonding with screen kids?
Zellweger: "Oh yeah, that always happens. Always. It happens fairly naturally, in fact we were fairly spoiled in that respect as well. Through the audition process Ron had brought us there so he could see what the natural dynamic would be like. And the children came and auditioned together, and there would be different combinations of children and the final triptych came together as a result of them singing happy birthday.
"The eldest pulled the rowdy, younger son in and the youngest was coddled by both of the older boys. It was just worked so beautifully, they were comfortable with Russell and Ariel was always on my hip if she wasn't working. She was always right there first thing in the morning with the hugs, and last thing. So there is definitely that.
Can you tell us about the difference between playing real and fictional characters? And, when did you first encounter Mae?
Zellweger: "I read the script in about 1997, I think that's when Russell had it in mind that he was going to get that movie made. I loved it and knew that it was special. Not only because the content was so moving but it was a true story and what was so fantastic about it was that you didn't have to talk about sensationalising that.
"These people lived and this was their life story and what it came to represent was phenomenal. It came to represent hope for an entire generation of people, it was fantastic. I loved it. Also I recognised how special it was, because they don't make movies like that any more, they don't make movies that are just about a couple of married people who love each other a lot, who inspire people to believe.
"Those are my favourite kinds of films, where you invest emotionally and walk away having a different perspective on your life, or life in general. I love the ability that a good film has to inspire in that way. And I knew this would. I didn't know so much about her but it began with hoping to be part of that project.
"And it's different to play a person who lived, because the responsibility is slightly different in terms of accuracy, and the [group of] people that you feel a responsibility to not let down is broader. You always want to be sure that you don't drop the ball for your co-stars and the people making the film and in this case [Mae's] family members and the people who knew her. So there was less creative licence.
Renee have you ever been to a boxing match, or shown any interest in the sport?
Zellweger: "No. I never had occasion to. I watched it with my father on tv, Muhammad Ali and Sugar Ray Leonard, and he appreciated it. So I'd watch it ever now and then, but I never really came to appreciate it fully until we were learning about it.
"Now I have a better understanding of it, and it's a much more sophisticated sport than I had recognised before. [I have] a new found respect of what those guys go through in terms of discipline.
Do you hope this film will be a history lesson of what life was like during the Depression?
Zellweger: "I sure hope so. I hope so, because it wasn't that long ago, and dire straits were ubiquitous. There is so much that is taken for granted these days, so much."