My play The Libertine is about John Wilmot, second Earl of Rochester, who was the leading figure at the court of Charles II. Rochester is now recognized as one of the major poets of the 17th century, but in his own lifetime his career as a womanizer, drinker, atheist, pornographer and rebel gained him more attention than his serious writing. He died of alcohol and syphilis at the age of 33 after making a late conversion to Christianity.

The American premiere of The Libertine was given in 1996 by Steppenwolf with John Malkovich in the lead role. Malkovich, with his immense stage presence and his flair for making dangerous choices, was an ideal Rochester, but from a playwright's point of view the most interesting feature of working with him was his ability to help refine the text in the rehearsal room. The play had originally been directed by Max Stafford-Clark for Out of Joint in 1994, but I was unhappy with the second half of the play and eager to make changes.

One of the problems was that Rochester's life, although short, was packed with incredible incidents. On one occasion, he posed as a quack doctor whilst in hiding after a drunken brawl which culminated in the death of a friend. He was incredibly successful and his phony creation, Dr. Bendo, became the talk of the town. Rochester was such a brilliant actor that no one suspected the quack's true identity, and the earl was able to make easy financial pickings and enjoy extraordinary sexual opportunities till the heat was off. Naturally, this episode cried out for inclusion in the play. But it involved a difficult gear change for the lead actor in the middle of the second act. I rewrote the scene twice during rehearsals (and discovered Malkovich's underexploited gift for zany comedy) but still the Dr. Bendo incident seemed to take us off the main highway of Rochester's physical and moral disintegration. After the second preview, John told me he had given it his best shot but it wasn't going to work and could I rewrite the middle of the second act by tomorrow? This I did and was deeply impressed to see Malkovich and the Steppenwolf company take the new material in front of an audience after a single rehearsal.

However great a playwright's experience, rehearsing with good actors will always improve the text. In this instance, the guiding light was Malkovich's insistence on finding a visceral line through the play—an emotional hook which would keep the audience emotionally engaged through every moment. This approach was echoed throughout the Steppenwolf company. In another scene involving a drunken brawl (there were many), Rochester and his cronies smash the King's sundial (at the time, the most expensive scientific instrument in Western Europe) to pieces. The actors took a long time preparing to rehearse this piece of violent physical action, then went for it and did it perfectly the first time. The director (my fellow English playwright Terry Johnson) could not persuade them to do the scene again until the first run-through. Where English actors tend to intellectualize, American actors are happy as long as they can find a gut instinct to take them through a scene. I feel very lucky to have experienced both approaches to the work.

I am delighted to have The Libertine published in this new edition as it has given me the opportunity to incorporate the Steppenwolf revisions.