HE'S the Oscar winning director of Gosford Park and is working on a brand new stage version of The Wind in the Willows with the team behind his previous smash hit musical Mary Poppins.

But there's only ever one subject on the lips of everyone Julian Fellowes meets - his critically acclaimed and multiple award-winning television series Downton Abbey, the very British tale of the aristocratic Crawley family and their servants in the early 20th Century.

The actor, novelist, film director and screenwriter, and Conservative peer in the House of Lords created the series which became a global phenomenon when it appeared on TV screens between 2010 and 2015.

And Fellowes has revealed fans may not have seen the last of the Earl and Countess of Grantham and their aristocratic antics.

"It's definitely the end of Downton on television," he tells me. "There won't be any more television shows, but we might make a film, I'm completely up for letting it continue. The problem would be rounding everyone up as they've all shot off to the four corners of the industry and the globe. Getting them together could be quite a headache, but not mine thankfully!

"I think it would be interesting for us to do something with a different structure, but recognisable. When a TV show decamps to Honolulu it never really works, so we'll have to see, but the great audience makes it worthwhile. "

The level of interest in the ITV show, which won a Golden Globe and an Emmy and has been screened around the world, shocked even veteran writer Fellowes, the author of several Sunday Times best-seller novels.

"It was extraordinary," he muses. "I was shocked at the level of success. I thought it was a good show and I thought it would work, but I thought it would be a case of finding its audience, I certainly didn't think it would take off like it did.

"In China and in America, the reception is just phenomenal. There are always people coming up to discuss it. It even happened once in Uganda! Who can expect that?!"

The 67-year-old is no stranger to phenomenal success. He is the proud recipient of an Academy Award for Gosford Park, his first screenplay. The 2001 mystery starred an ensemble including Helen Mirren, Maggie Smith, Michael Gambon and Clive Owen and told the story of a murder following a dinner party at an English country house.

"It was like a fairy story. The first award I won for it was the New York Film Critics Award and that was a great honour. I was actually very very thrilled by winning that and as it was early in the season that really projected me onto the awards circuit. Before I knew it I was up for an Oscar and won it. It seemed an extraordinary series of events and I couldn't really believe it."

His latest project is the book for a spectacular new musical version of Kenneth Grahame's much-loved novel The Wind in the Willows, which will visit Southampton on its world premiere tour this month.

"When Jamie (Hendry, producer) came to me, I felt the time was right for a new version as a musical. It's been a straight play over the years, but not a musical before. It's got a new book, new music and everything new. I had already heard George Stiles and Anthony Drewe had written the lyrics. I worked with them on Mary Poppins a few years ago and found the idea of re-uniting appealed.

"I also liked the idea of working on an iconic book that everyone's heard of, even if they can't remember it. It was certainly part of my childhood, I had it read to me in the bath! I love the book because of the theme of friendship it explores. If you think about it, that's very rare. Most tales are about love and friendship is secondary.

"It's pretty faithful to the book, the only real change is that Otter is now Mrs Otter so that one of the principles is a woman. That was done partly musically to have a woman's singing voice in the mix, but I think it's also of the time. It seems a healthy change to me and we haven't substantially altered anything else."

The Wind in the Willows is sure to be a huge success, just like pretty much everything else Fellowes has ever put his name - and pen - to.

His own personal favourite is not any of the global hits he has worked on.

"Separate Lies," he doesn't hesitate. "It was my debut as a director and I found it all terribly exciting. I won an award for it and I was in the middle of all these people like George Clooney and Lauren Bacall. It's my personal favourite of everything I've done. It did well on DVD, but it didn't have a huge audience.

"It had wonderful performances from Emily Watson and Rupert Everett. Steven Spielberg said you should always make films you want to see and I think that's true. This is exactly my type of film about a perfect couple who should have everything but in fact are coming apart."

One of the most celebrated writers Britain has ever produced, I discover during our conversation Julian Fellowes is also one of the most humble. He doesn't even consider himself the prodigious talent he is widely considered.

"It's all pretty uphill for me, it doesn't always come easily. But I'm not going to complain as I know I'm very fortunate. There are people out there doing jobs they find very trying and not interesting at all.

"There are lots of writers far more talented than I am that haven't had the lucky break."

For once, we beg to differ Lord Fellowes.

The Wind in the Willows runs from November 10 to 20 at Mayflower Theatre.

Tickets: 023 8071 1811 or mayflower.org.uk