When Hollywood and Theatre collide, the hot spotlight of celebrity-driven media turn to the stage in anticipation - Nicole Kidman disrobed for her British stage debut in The Blue Room in 1998 and Daniel Radcliffe followed suit (or should I say birthday suit), with his nude exploits in Equus.
Blanchett has been the latest star to step away from the film studio with Gross und Klein.
As glossy magazine journos become guest culture reviewers, serious theatre critics are drawn to a similar role reversal, as they question whether a big star can sweat it out without retakes and slick editing and still come up with the goods.
A tough cynic would label a star's indulgence on the stage as a tick on a career check list; reassuring themselves that they have stayed true to their art form, free from creative guilt as they return to their pension-paying perfume adverts and rom-coms.
But Blanchett could not be a million miles further from being a theatrical tourist - the actress became joint artistic director of The Sydney Theatre Company in 2008 with her playwright husband Andrew Upton and has poured her energy and expertise into theatre productions for the last five years, while her film credits have been thinning out.
The Cate that won international fame as the Virgin Queen in Elizabeth, wove Elvin magic in The Lord of The Rings and achieved Oscar success playing legend Katharine Hepburn in The Aviator - that very same Cate is serious about theatre.
The seasoned professional appeared on a recent front cover of The Economist magazine Intelligent Life in an honest portrait that sidestepped makeup or Photoshop trickery - the strapline reading: "This is not a film star. Cate Blanchett, theatre boss."
Blanchett told Intelligent Life about her theatre life: "I haven't really been able to make any films... I'm committed to acting on stage and have done it at least once a year, and that means on a very prosaic level not putting the children to bed for six weeks, so then I don't really want to go off and make another film."
Performed in the sumptuous cultural haven of the Barbican centre, Blanchett immediately shows she can hold the play by herself in Gross und Klein, as her character Lotte Kotte opens the first scene sitting alone on the edge of the stage, in what could be a one-woman show. Lotte strains to hear unheard sounds, and then declares: "Hear that? Outside. Two men, pacing up and down, endlessly."
Lotte listens to two men outside her window, developing a crush on the disembodied voices. As she girlishly confides in the audience, we discover her to be skittish and likeable, but vulnerable, with demons to face.
We embark on Lotte's journey as she comes to terms with a failed abusive marriage and tries to escape painful memories, feelings of abandonment, jealousy and isolation, that haunt her new single life.
Played out in a dream-like, Alice-in-wonderland-style narrative of disjointed scenes, we are treated to plenty of post-modern rhetoric, reminscent of Samuel Beckett's Waiting for Godot. In one section, Lotte moves from one apartment room to another, interrupting bizarre scenes, such as an agressive tent that chases her across the stage and a heroin addict having a fit while watching tennis; presumably a myriad of symbolism and metaphors.
Watching the angst of Lotte's fracturing mind, Gross und Klein is not always a recipe for happy viewing. In one scene, Lotte writhes on the floor of the stage in a sparkly gold costume, arguing with God, who she fears wants to fill her soul and ultimately destroy her.
But Gross und Klein's stand-out strength is the sharp contrast between the dark moments of tragedy and delightful laugh-out-loud moments of comedy. This is where Blanchett truly excels, bringing us back from a bleak edge to slapstick goofy humour. Funny moments include Lotte as an office assistant dating her manager - she is so delighted in her new situation that she skips child-like between desks as she proves hopeless at typewriter dictation, much to the chagrin of her boyfriend struggling to cope with her eccentricities.
Like most post-modern plays, Gross und Klein's cryptic meanings are not immediately clear and makes for a second-viewing or textual study to fully appreciate writer Botho Strauss' intentions. Supported by a strong cast, it is Blanchett's exceptional performance as Lotte Kotte that leaves Gross und Klein lingering in your mind and wishing you could watch it all over again.
After London, Gross und Klein moved on to performances in Vienna and Recklinghausen as part of the play's European Tour.
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