Once celebrated and feared as the bad boy of filmdom, Orson Welles was a brilliant director so difficult to work with and so personally erratic that following his first movie, the monumental Citizen Kane, he never again made a movie in Hollywood that wasn't controlled and butchered by the studios. Simultaneously egotistical and emotionally fragile, Welles, with only sporadic moments of post-Kane brilliance, was ultimately reduced by the end of his life to spoofy walk-ons in The Muppet Movie, bizarre meteor-toting appearances on The Tonight Show and those terrible Gallo wine commercials currently enjoying a vogue on Youtube.com.

In Orson's Shadow, now in its Northern California premiere at the Marin Theatre Company, playwright Austin Pendleton has devised a fascinating way to muse upon the tragicomedy that was Orson Welles' creative life, piggybacking onto the similarly loose-cannon mind-set of that other emotionally contradictory acting genius, Laurence Olivier. Taking a little-remembered footnote from film and stage history, Pendleton re-creates the moment in the early 1960s when Welles' friend, the English theater critic Kenneth Tynan, persuaded him to direct a London production of Eugene Ionesco's Rhinoceros, starring Olivier and his then-mistress (and future wife), Joan Plowright. The resulting clash of egos and wounded psyches nearly swamped the whole production, made more complex by the fact that Olivier was at that point married to the mentally unstable actress Vivien Leigh, of Scarlett O'Hara fame.

In Orson's Shadow, thoughtfully directed by Lee Sankowich, Welles, brilliantly and soulfully impersonated by Steve Irish, is still smarting from the bad reviews and empty houses that met his disastrous original work Chimes at Midnight, a grandiose variation on Shakespeare's Henry IV. When an ailing Tynan (Liam Vincent) appears backstage to encourage his troublesome friend to take the job directing Rhinoceros, the show kicks off in an entertainingly farcical tone with Tynan addressing the audience.

Welles' first appearance is, as the title suggests, as a shadow, thrown larger than life across the stage floor as his stentorian voice booms down from an upstairs dressing room. This early scene, enhanced by the pleasantly clueless backstage hand Sean (Zac Jaffee), is a verbal jousting match between Tynan and Welles. Once Welles agrees to direct Olivier, with whom he has long had a love-hate relationship, and whom he now blames for his failure in Hollywood, the action shifts to the Royal Court Theatre in London, where the biggest battles of the play take place.

Plowright, an arch and watchful Deborah Taylor Barrera, and Olivier, played with magnificent manic energy by Nicholas Hormann, are experiencing their own series of relationship issues. The sexy-maternal Plowright expertly caretakes the great one while absorbing the heartbreak of his lovestruck stories about his crazy wife, who, of course, finally shows up to spread more comic drama.

Played with surprising decency and respect by Amy Resnick, Vivien Leigh is at once bonkers and wise, the only character who seems to recognize what all of these fragile egos really need and how they can drop their petty worries and grudges and get down to the work they are famous for: creating brilliant art on stage and screen. In its final moments, Orson's Shadow becomes startlingly moving, proving itself to be a love letter, of sorts, not only to the quirky brilliance of Olivier and Welles, but to the ridiculous, incalculably neurotic beauty of the creative process itself.

'Orson's Shadow' runs through Oct. 8 at the Marin Theatre Company. Tuesday and Thursday-Saturday at 8pm; Wednesday at 7:30pm; Sunday at 2pm and 7pm; also, Sept. 20 and 28 at 1pm; Oct. 7 at 2pm. Sept. 20 at 6pm, singles night reception. Marin Theatre Company, 397 Miller Ave., Mill Valley. $19-$47; Tuesday, pay what you can. 415.388.5208.

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