PATRICK Stewart, esteemed Royal Shakespeare Company thespian and Star Trek captain of the Next Generation, had already signed up for the Playhouse revival of JB Priestley's Johnson Over Jordan when he offered an aperitif: the British premiere of his one-man show Shylock: Shakes-peare's Alien.

It takes the form of a think piece with speeches from the play, followed by a post-show discussion with a guest inquisitor, in which the snowy-bearded Stewart switches from formal business suit and lectern to jeans and comfy chairs in the company of Philip Roberts, Professor of Theatre Studies in the University of Leeds.

Stewart, the 60-year-old West Yorkshireman from Mirfield, has played Shylock, Shakespeare's "stage Jew", twice in his 50 years on stage, television and film, and both of them longer ago than he might wish to recall. Yet the role has stayed with him: first as the subject of his essay for a guide to playing Shakespeare and then in Shylock: Shakespeare's Alien, a piece so flexible, open to constant re-analysis and compliant to detours - this time it was the Wimbledon tennis championships - that last night it ran to a record 88 minutes. And the post-show reflections were still to come!

Stewart's first encounter with the money lender of The Merchant Of Venice had been at the tender age of 23 or 24 at the Bristol Old Vic. The experience has been one of panic and "being trapped inside a strait jacket".

During his 17 years at the RSC he was offered the part again, and his initial reaction was disappointment. Why? He didn't consider Shylock to be one of the top-ranking roles (it involves only five scenes, one of them 17 lines of blank verse); he spends more time merely saddled up rather than riding. Add all the Jewish baggage associated with The Merchant Of Venice, and director John Barton's belief that "Shylock fundamentally had to be a monster", and Stewart was hardly champing at the bit. Yet he ended up playing him for two "exciting" years, Olivier Award nomination and all.

Stewart's show recounts how he researched, prepared and performed the role: giving an insight into both Shylock, the character, and Stewart, the actor. He notes Shylock's humour (he decided to make him an entertaining monster); he describes the state of "contrived innocence" needed to play a part for the second time; he jokes about his lack of empathy with Greek drama and how acting is very expensive nursery playing. He even offers advice for life from an old tutor: you will never achieve success by only ensuring against failure.

Patrick Stewart would make a marvellous teacher; Shylock: Shakes-peare's Alien is an inspiring, revelatory first lesson.

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