Sir Tom Stoppard, 70, is an award-winning screenwriter and playwright. He won an Oscar and Golden Globe, and was nominated for a Bafta for co-writing Shakespeare in Love (1998). His play The Coast of Utopia won a Tony in 2007 and critics hailed his play Rock’n’Roll in 2006. He was appointed CBE in 1978 and knighted in 1997. Other screenplays include Empire of the Sun (1987) and Enigma (2001).

The producer Edward Zwick already had a script for Shakespeare in Love from Marc Norman. Universal asked me to look at it and see if I could do something with it. Studios assume that you’ll like to do something on the basis of whatever your last project was, but that isn’t always the case: you might want to try something new.

The film took a long time to be made. It was five years between me finishing my script and the film being released. For a long time Julia Roberts was interested in doing it [as Viola De Lesseps, eventually played by Gwyneth Paltrow] if Shakespeare was cast in a way which met with her approval – she wanted Daniel Day-Lewis. Sets were built at Pinewoood. But Day-Lewis didn’t want to do it and the script kept going around.

I wrote it as a pastiche of showbiz and show-making. There were lots of in-jokes but not so “in” to put off those not in the business – a poster for Romeo and Julietmentioned anything but the author. John Madden [the director] made it into the success it became: both he and Harvey Weinstein [co-producer] saw it as a romantic story that was also funny, rather than a romantic comedy. The love story, and the way in which it was told, became the film – rather than a hundred decent jokes with a couple of lovers thrown in. When you see screenwriters credited at the end of the film, if their names are linked by an ampersand they wrote the film together, if their names are linked by “and” they have never met – I didn’t meet Marc until a day of shooting in Windsor, where we both discovered we shared a love of flyfishing. I see myself as a playwright and not a natural screenwriter. It took me years to think cinematically. You have to realise, when writing for film, that you are totally liberated. I tend to forget and advance things by having two people talk together on a bench. The whole thing of letting the cameras move and deploying information (in some cases in a less linear, more fragmented way) can be very different in films.

Almost always the film is taken away from the writer. It shouldn’t and needn’t be. The writer has a responsibility here as well as the director to be available. I don’t think I’ve had a happier relationship with a director than with John Madden on Shakespeare in Love. He didn’t want to take anything away from me. He just wanted to add to it. We had so many discussions and he was extremely solicitous about letting me know about changes.

I like the early stage of screenwriting, the first and second drafts. I am an optimist: each time I think it will go perfectly and every time I will write a script that everyone loves. It never quite works out like that; there is always a slight disappointment. Many people have asked me to adapt my own plays for film. But one seems to fall between two equally awkward stools: you film the play and end up not satisfied with the film, or to make the film you leave out two thirds of the play, so why make it as a film in the first place?

People have often wanted to make The Real Thing into a film, but I’ve resisted because I have no appetite to do it myself and I couldn’t bear to have anyone else do it.

Shakespeare in Love was an original; the other films I’ve written have tended to be adaptations of books. One has to make severe choices.

With Empire of the Sun, Steven Spielberg decided the relationship between the boy and John Malkovich’s character was central, but there were many other spokes to the book. As the screenwriter, that’s an example of having to hand over authorship to the director. It’s something I knew before I got into it.

Of course, if it was the theatre, it would break your heart. I wrote the first draft of The Golden Compass, but no director was attached to it. Ultimately it got a director [Chris Weitz] who liked to write his own scripts. He never even read mine. That was a little frustrating, but I went into it with my eyes open. “Let it go”: that’s the way to see it. Don’t feel that you need to follow a screenwriting rulebook. Write from your own inspiration.

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