Simon Callow: Now Mr Nice Guy has turned nasty

Simon Callow's role in The Holy Terror is a startling departure for the normally cheerful thespian

Simon Callow played Hitler at the dawn of his career in Bertolt Brecht's play The Resistible Rise of Arturo Ui, in 1978 at the Half Moon Theatre. But in describing his latest role as Mark Melon, the cunning publisher who hits rock bottom in Simon Gray's play The Holy Terror, Callow says: "I have never played a more ruthless modern-day character as this."

Nowadays, such a role is something of a departure for the actor, director and author whose more sympathetic characters include the flamboyant Gareth in Four Weddings and a Funeral (1994), and his roles in Merchant-Ivory's A Room with a View and Maurice in the 1980s.

"This character is not just ruthless, he's also brilliant, sexy, very successful, intuitive, imaginative and cuts through a lot of garbage to win publishing deals - and makes money," says Callow of the role. "But he tramples on many people and is sexually voracious, a side not known to his wife, and goes too far.

"He starts to destroy everybody - and destroys reason - until he has a mental breakdown. His mania is revealed in insane jealousy towards his wife. Although I have met many people like this - you see it all the time in the theatre world - I haven't had to research the character because it is written so well and the play is so mercurial due to a series of flashbacks," he says.

Simon Gray, who wrote The Holy Terror, is a prolific playwright. His stage plays include Butley, Otherwise Engaged, Quartermaine's Terms, The Common Pursuit and The Late Middle Classes. His latest book, The Smoking Diaries will be published this spring. While the director, Laurence Boswell has recently directed Up for Grabs, A Day in the Death of Joe Egg and Popcorn. This is the first offering from Boswell's Brighton-based production company and it plans to stage up to three new shows each year, which will launch from Brighton and tour the UK before hitting the West End.

Callow's acting career began in 1968 when he wrote to Sir Laurence Olivier, then running the Old Vic theatre. "I told him in a three-page letter how brilliant his theatre was," says Callow. "I said it made one proud to be British - in an attempt to win him over. He replied and said if I liked it so much, there was a job going in the box office, which I took."

But does he prefer working in theatre or film? "To work with an audience is a gratifying experience, and instructive. The audience teach you about the play and you can be better than the night before," says Callow. "In films, it is just you and the director. A performance is more set in stone. But each is good."

His favourite part so far has been in Manuel Puig's play Kiss of the Spiderwoman in 1986. "I played Molina, the hysterical queen locked in a cell with a transvestite."

Of his current work, Callow adds: "Although the events in The Holy Terror are verging on bleak, Simon [Gray] tells it with such sardonic and witty relish that it is a funny play. It is fairly chastening at the end, but exhilarating to watch and certainly exhilarating to act in."

'The Holy Terror', Duke of York's Theatre, London WC2 (020-7836 5122), opens 14 April