Ian McKellen believes in the theatre.

He calls the UK the “theatre centre of the world”.

It was on the stage McKellen was first intrigued by acting.

“I wanted to find out how it was done,” he says.

If the art form, almost as old as the written word, is to continue, it needs more film superstars’ support.

Some actors see stage work as a chore. Once they have migrated to a world of international acclaim they cannot return to where they can see and smell the audience.

The Burnley-born actor – who gave life to Gandalf, Richard III and horror film director James Whale on the big screen – is currently playing Don Antonio Barracano in Neapolitan playwright Eduardo De Filippo’s The Syndicate at Chichester’s Minerva Theatre.

To him, to return to the stage is a thrill.

“I’ve been very, very lucky – perhaps rather late in life – to be able to work in all the different mediums.

“Each has its own challenges and, although I can’t imagine not working in the theatre, I know a lot of actors in my generation who think, ‘Oh, it’s so much easier to do a film’.

“You get very well looked after as a film actor. There’s a car to take you to and from work, there’s free food and, as for the responsibilities of being on form the moment the curtain goes up, it’s not quite the same in that it’s a little bit more leisurely in the cinema.

“But, of course, for anyone who likes the theatre, the thrill of hearing the audience and looking forward to telling them the story doesn’t go away.”

In between filming The Hobbit, a two-part adaptation of JRR Tolkien’s 1937 fantasy novel which is directed by Peter Jackson and a prequel to The Lord Of The Rings film trilogy, McKellen has been on stage in Sussex.

In 2009, the tramp he played in Samual Beckett’s Waiting For Godot was so convincing one felt Estragon could have just walked in, lost, from the street.

“Before I agreed to return to Gandalf the wizard, I said ‘Look, I must be able to do a play’ because I don’t feel quite sustained as an actor unless I’m looking forward to doing a play.

“So I’ve just come back from New Zealand [where The Hobbit is being filmed] especially to do this play and I’m just managing to fit it in and go to Chichester and do the tour.

"I’m at an age where I think I’m still fit. But I think, I don’t know. Any day now I might break an ankle or break a leg or something might happen to me and I won’t be able to work again in the theatre at the rate I do, so I’m just very happy to be doing it.”

Age is something McKellen, now 72, has in common with Don Antonio Barracano – also in his 70s– a stylish mafia boss who is trying to police the Naples streets along the lines of his skewed moral code.

The two have a similar work ethic too, and because Don Antonio is unlike other mafia heads – he has a conscience and wants to avoid violence – McKellen can work his versatile style into De Filippo’s witty script.

“Eduardo De Filippo is one of the great forces of European theatre and he’s been a little bit neglected in this country. He’s still immensely popular in Italy and I’m sure there’s a production of The Syndicate going round there as we speak.

“I think as you sit there you think, ‘Oh! This is what a well-made play is’, and we’re finding in rehearsal that it’s not like doing a new play – ‘Oh, I wonder how this is going to work’ – you can absolutely see why this works: the dramatic climaxes are tremendous.

“The comedy is firmly in place. All the different characters with their problems and how Don Antonio helps them are clearly on display. It’s a very easy play to sit back and enjoy. But it’ll give the audience a few shocks en route to the climax, which I won’t spoil by saying what happens.”

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