Story highlights Kate Maltby: Film actors aren't as confident editing their own scripts as they like to think

When you need to improvise for real, you'd better be able to do it right, she writes

Kate Maltby is a regular broadcaster and columnist in the United Kingdom on issues of culture and politics and is a theater critic for The Times of London. She is also completing a Ph.D. in renaissance literature, having been awarded a collaborative doctoral between Yale University and University College London. The opinions expressed in this commentary are hers.

(CNN) Janet Jackson endured a wardrobe malfunction -- and Warren Beatty now knows all about a script malfunction.

All great stage actors can handle the unexpected, whether it's a forgotten line or a lost prop. They are trained to improvise and, following a decent rehearsal process, are usually on stage with colleagues they trust implicitly to pick up the pieces and react to their unspoken cues.

After opening it and scrutinizing the card inside for an age, he leaned into the microphone and declaimed "and the Academy Award for Best Picture..." before thrusting the card like a coward towards his Bonnie and Clyde costar, Faye Dunaway -- even though an ounce of initiative would have told him what had happened.

In my career as a theater critic, I've seen lots of things go wrong on stage. I was impressed by the actress who, forgetting her lines in the high-profile press performance of a production of Sheridan's "The Rivals," simply held position and called firmly out to the wings: " Can I have a prompt, please?" Admitting when there's a problem always wins points for honesty. Beatty, ever the attention seeker, compounded his error by grabbing the spotlight back at the end of the show and attempting to justify his behavior.

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