Hollywood star Julia Roberts suffered an "apoplectic" attack when she had to film her first scenes as a public speaking professor in new movie Larry Crowne - because she found the experience terrifying.

The actress plays a boozy teacher in the upcoming comedy/drama, about a middle-aged man, played by Tom Hanks, who goes back to school after losing his job.

But Roberts, who didn't go to college, insists shooting her classroom scenes in front of her movie students was a nerve-wracking nightmare.

She tells W magazine, "This was my first college experience. And the first time I had to speak in front of a classroom, I was apoplectic. All these faces looking up at me, thinking, 'What is she going to teach us?'; I needed to find my composure. It was very hard - it was terrible, in fact."