What made you want to be part of this drama?
Well, I was really excited to hear they were making a drama about Barbara’s whole life and, having played her before, I was really interested to find out more about it. When they sent Tony Jordan’s script to me I thought it was such a clever way of telling her story and it was so beautifully written. Then I met up with Dominic [director] who had some fantastic ideas and he seemed to have a very delicate touch, so yes, I really wanted to be a part of it.

You’ve played Barbara before - when you took on this role did you want to play her the same way or did you try and do it differently? Or was it just natural to become Barbara again?
It's interesting, because the part of Barbara that I play in this film is the Barbara that people don’t see much, because in this she is subdued and thoughtful and quite morose at times. Last time [in Cor Blimey] I played Barbara during the Carry On period, so it covered a wide range of the younger Barbara. It was an exciting challenge this time to play the more mature, more thoughtful and troubled Barbara.

Was it hard playing parts of the drama when you, Nick and Jaime, and sometimes Barbara, were all in the same scene but not always all aware of each other?
Exactly, it 's a bit like the Christmas Carol thing. For me, I was aware of Nick, but Jaime wasn’t. Was Jaime aware of me? No. Was I aware of her? Yes. So it was just knowing what the conventions were, and then not getting too worried when the rules got broken, as they did.

Did you know Barbara before you took on the role?
I met Barbara and got to know her last time I played her, and she was unbelievably generous. She arrived backstage after the first night of Cleo, Camping, Emmunelle And Dick with flowers, chocolates, a balloon, champagne and a camera crew - typical of Barbara! She was really open to me phoning her up at any point to ask for any information or advice. So it was lovely coming back because we already had a relationship - but this time spending time with her and Scott has been really amazing. They are both unbelievably supportive and loving and I think you can see the influence of that in the film. We all have the hugest affection and admiration for both Barbara and Scott.

Does that add to the pressure do you think?
It really didn’t. It’s weird, if I was looking at that situation I would have thought - crikey that must have been a really pressurised - when Barbara was there and Jaime and I were both doing our best to BE her, but what’s odd about it, it was the opposite. She was just always nodding and smiling and saying “it’s more like me than me!" and Scott as well, saying it was absolutely how it was when he first met Barbara. So there was never a feeling of “I wouldn’t do it like that” kind of thing. Barbara was always supportive which was amazing. I can’t imagine there are too many people in her position that would be like that. Barbara really is unique.

Did you do any research for the role? Did you study any of Barbara’s work or interviews?
The first time I played her I watched everything she’d done, from the early films all the way through the Carry Ons and then EastEnders, and of course all the wonderful interviews. There is an endless amount you can watch and it is all extremely helpful. So this time it was tapping back into that and also being very specific about the period, the early 1990s when there’s not as much of her. There is a fantastic This Is Your Life when Barbara was married to Stephen (Hollings) and a few interviews that were very, very helpful, which I just loved watching. It's fascinating finding a little moment that becomes a sort of hook, rewinding it and then watching it over and over and then letting it wash over you until it becomes part of you.

Was Barbara there when you auditioned?
No, not for either time I have played her. Barbara is always clever like that and that again is her being generous. Barbara wouldn’t want to put people under that sort of pressure, she doesn’t really like to take the limelight in those situations. She takes a step back, she is a very classy lady like that.

What was the biggest challenge you found when taking on this role?
The biggest challenge was playing the Barbara that people don’t see and that people don’t know, and being brave enough to take the foot off the accelerator and just let her just be. Not worry too much about the impersonation or what people are going to think, and let the writing come through, as opposed to putting too much on top.

Did you and Jaime speak before you started filming about the way you were both going to play her?
From the moment Jaime and I met we started feeding off each other in how we would be playing Barbara. It was sort of by osmosis. We did talk a lot about it and we really worked together towards becoming the same Barbara, as opposed to going down our different avenues. Luckily we got on extremely well and I think watching it, it doesn’t feel clunky when it goes from one Barbara to another. And with little Honor as well, there is fluidity to it which I hope people feel, as we did.

Did you compare the giggles?
I think we did! We made a conscious effort to portray her in the same way, because there are lots of different Barbaras and we could have just been in our own little tunnel, and that might have been a bit jarring. Luckily the first two weeks of the film we were with each other every day and we were watching each other every day, so we were just growing together which was lovely for us both. It was an absolute pleasure.

I think there was a very weird moment for Scott (Mitchell) when he saw the three of us on stage all giggling. That must have been very surreal.

Do you think it is harder to portray someone who is such a national treasure?
As long as you’re not scared it actually makes it easier. You know, one can be put off doing something that people are obviously going to scrutinise, but the positives are, there is so much to throw yourself into and research, and there is such a great affection for Barbara, so why wouldn’t there be great affection for the piece?

Did you enjoy stepping back into that era and wearing those costumes?
No (laughs). I think it was probably great fun for Jaime going through the 60s - that’s a fantastic era. The 90s - I don’t think anybody comes out of too well (laughs). It was fun but I don’t think a purple jumpsuit does anyone any favours.

Did it help having Barbara around when you were filming?
It really did, it was an absolute joy. Everybody perked up when Barbara was on set. Everybody was thrilled. She took time to talk to everybody, she knew everybody’s name. Barbara is such a pro and such a star that every time she was around we just all wanted to make her happy and you hope she was pleased with what we were doing. It was an absolute pleasure to have her on set.

What was it like working alongside Jaime and Nick?
It was lovely, we had such a laugh. Jaime, well, I have just completely fallen for her. I think she is wonderful and I would love to play her mum one day. I feel there is something similar about us which is probably why we have both been cast to play Barbara. Whatever that is, I don’t know, but I adore her. Nick and I had a fantastic time together, we both really enjoyed being interrogative with the detail. I have to say, the whole cast was a joy.

Dominic [the Director] was just brilliant to work with. He is such a lovely man and extremely clever. The great thing about him is he always had time for everyone, the actors, art department, camera, costume, props, everyone - you never got the feeling he was under pressure, which he must have been, but he was always interested in what everybody had to offer, which I think you can see in the film. It was an unusually enjoyable experience watching it. Jaime and I watched it together. You are normally extremely critical of your own performance and you can’t enjoy the piece as a whole, but we both really, really did. We were both swept along with it and the journey the film takes you on. We sat squeezing each other’s hands, one second laughing and the next sniffing.

What do you think makes Barbara so iconic?
Barbara is iconic because she truly is an original. Like it says in the film, 'she’s just got something' and it’s really hard to pin point what it is. She’s sexy, she’s cheeky, she’s funny, she’s a great actress, she is a great dancer, a great singer, she can do comedy, she can make you cry. She is a complete original. There is nobody like Barbara Windsor. She has been in the hearts of the public for many years, adored by young and old, men and women, you can’t get overwhelmed by it, but it is a real honour to play her and Jaime and I were so aware of that. It is a very special task and we are both extremely grateful for it.

Click here to read an interview with Jaime Winstone