The 2009 TIME 100

Zac and I shot a movie called Me and Orson Welles about a year ago on the Isle of Man. As soon as Zac arrived, it seemed more like the Isle of Teenage Girls. Many, many teenage girls. When Zac was first spotted through the window of a local café, a handful of admirers multiplied into a squealing mob. He had to be escorted back to the hotel in a police car. For almost a week, girls raced from school to keep vigil outside the hotel. I often fell asleep to their resounding chant: "We want Zac! We want Zac!" I have never worked with anyone so famous.

I couldn't help being reminded of the time I had spent with another gifted idol, Leonardo DiCaprio, about a decade before. I saw the simmering ardor of the teenage masses turn into unbridled hysteria after Titanic was released. But this was even more intense. The difference, I realized, was that Zac is not only an actor but also a musician, a bona fide song-and-dance man. We ladies are defenseless against such a combination.

But I suppose we all know that Zac, 21, is a song-and-dance man. What is less known — and what I had the privilege of learning firsthand — is that he is a performer capable of great subtlety and vulnerability. A lot is asked of Zac in this role. He plays a high school student from the 1930s who talks himself into Orson Welles' production of Julius Caesar and is seduced by art, the big city and, of course, a girl. Zac is in every scene; he recites Shakespeare, falls in love, discovers the expanse of the world, sees it suddenly collapse upon him and then goes back to high school. In other words, he becomes a man.

Zac met these demands with focus, humility and enthusiasm — and the result is breathtaking. It seems Zac is not only an entertainer but also an artist. He is going make us swoon for many years to come.

Danes will next star in the HBO film Temple Grandin

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