Were you proud of Wedding Week?
"Completely proud of it. I was ecstatic with it. It's one of the best weeks of episodes that we've done in a long time. With the Whitney week that we did last year and the Max and Stacey reveal at Christmas 2007, it's one of the peaks of the last few years. Everyone had a view on it and everyone who watched it had an emotional response of some kind to it. I've said it before, but that's all you want as a producer - you want people to connect to the material. I know not all those connections were positive, but I don't mind."
Did you cry?
"Of course. When I watched it, I had my head in my hands in a good way! I knew it wasn't going to be easy and I knew that a lot of people would be wrapped up in the story and heartbroken at the outcome."
Just to quash all the rumours, can you confirm that Danielle's definitely not returning?
"No, she's dead! We've seen her body, we've seen her coffin and now she's six feet under. There's no clone, there's no twin, there's no second daughter - and there's no Bobby Ewing in the shower! Only once before has this show bent the laws and that was with Den. I know I've been harsh about that in the past, but it was actually fun what they did."
"We're not planning a substance abuse route for Ronnie. It's been an interesting journey for her. She's found the daughter she's been looking for all this time, but she's found her too late. It's devastating and she wants to move on. She's been heartbroken and it's tiring for her to be sad. She wants to find happiness in love, so perhaps Jack can persuade her to give it another go with him? I think that recent events have awakened her need to be a mother and thoughts turn in the next few months to motherhood and whether she'll get the chance to be a mother again. And more importantly, if she does, who with. It also sends her back into the past. I'm not going to say we'll be seeing Joel or not, but we'll definitely be talking about him. After all, Joel's the only remaining link to Danielle.
"Archie will also be back and it'll be interesting to see if there'll be a reconciliation with his daughter. It's harder than ever now for the pair of them. They were really getting somewhere just before the wedding, but Archie's got a long way to go."
There's been a lot of talk since the end of last year about October 2009. What do you have planned?
"What happened was, at that point, we had this really exciting story planned for October 2009. I imagine October will be very, very good - and don't worry, it's not that the whole Square is going to burn down - but the particular explosion I was talking about has crept into September. When I originally said explosive, I meant emotionally explosive. Anyone expecting a huge conflagration will be disappointed! You might see Dot lighting a fag, but that's as explosive as it's going to get. It's always dangerous to talk about storylines a year ahead!"
When and what can we expect to see in Tony's trial? Will Chris Coghill be returning?
"That should play out this year, but we've not quite plotted it yet. Chris said to me some months ago that, in principal, he'd be keen to come back. I'd love him to return, and in due course I'll be having that conversation with him. How it plays out on screen remains to be seen. We still need to do our research. What's worked so far for us with this story is that we've stuck to the research and turned it into a story. The key to getting the trial right is being forensic with the research and we're still doing that. But we absolutely intend to honour the long-term truth of the story. If we didn't, it would be crass and lazy."
"What makes Sam interesting for me is that she's Ricky's first love and first wife. As Bianca and Ricky spend more time together and have more shared experiences around Tiffany and Whitney, the inevitability of them at some point coming together increases. What's stopping them? Well, it's Sam. Sam and Ricky had a good thing going all those years ago. All Ricky ever gets off Bianca is indifference, whereas Sam - and who knows quite why - is less than indifferent towards him and it makes a nice change…
"And the other thing is, who's the original Mitchell sister? You have these two pretenders in there with Ronnie and Roxy, but Sam is Peggy's little girl, her princess. Sam's Grant and Phil's sister, not these two upstarts. Also, Minty was obsessed with Sam, don't forget. The biggest thing we've got to get over, though, is the fact she's on the run in Brazil. We'll definitely get around that one - we've got it all worked out…"
EastEnders' 25th anniversary is just around the corner. Have you already started planning for it?
"We have actually planned it. I know exactly what the week of the anniversary is. All I can say is that all the dramatic values of the last 25 years of the show, everything that has made EastEnders the phenomenon that it is, we're hoping to evoke in that week. It's a celebration of the show, not necessarily, but not excluding, a trip down memory lane. It's more the values of the show, what people love about it."
Albert Square seems to be lacking a young alpha male character since Sean's departure. Any plans to fill his shoes?
"To a degree. I think we've got a few people filling those shoes. Let's just say that by the summer, there's going to be a significant infusion of young men…"
There are a lot of people who say soaps are starting to rely too heavily on past characters. What are your thoughts?
"Over the years, there have been some absolutely brilliant characters played by brilliant actors who aren't in the show anymore. When there's a story for them and they're up for it, why not bring them back? The audience loves them. With Ricky and Bianca, people grew up with them and to see them 15 years on… It shouldn't be that the only thing we ever do are returns, but with a show with as rich a history and as strong a back catalogue as we have, there's an element of EastEnders Allstars about it. It's fantastic."
"We've got a fantastic young cast at the moment. There's this group of kids going down in age from Darren and Libby, to Whitney, though Peter and Lucy, Lauren, Abi, Jay, Ben and Tiffany. I see them as our youth squad. Like a football manager, you develop a younger team and it's really exciting that people like Thomas Law and Melissa Suffield are doing so well. I love how Charlie Hawkins has really blossomed and made that difficult transition from child actor to adult actor. It bodes really well for the future. My era saw Ian, Sharon, Michelle, Kelvin and Wicksy coming in, Mark… I loved that group of kids. It's probably them that hooked me in as a 15-year-old."
Last time we spoke, you'd been doing some test filming in HD. Have there been any developments?
"What we've concluded is that everything is there for us in design terms for us to upgrade to HD apart from the exterior set, which is 24 going on 25 years old. And it shows, particularly in the brickwork on the Square and Bridge Street which doesn't pass muster on HD. Until we've either completely refurbed the exterior set or moved the programme somewhere else and built it from scratch, then we're not going to be going HD."
And what's the latest on the set move?
"I'd love to pretend that it was in any shape or form my decision, but it's tied up in lots of very big questions for the BBC regarding finance, property and how to best protect one of the corporation's greatest assets. It's a complicated question, but there's been no decision made either way."
> Click here to read Diederick teasing as to what's to come for the residents of Walford