Virginie Ledoyen pretty much sums it up when someone asks her the question that goes: "What was it like working with Leonardo DiCaprio?"

Actually, it is pretty much the only question being asked in that cramped little room in the Kempinski. And it will likewise later be asked, over and over again, in the zoo of a press conference which follows in the Palast. That, and the question that is put to the star himself, which goes: "What's it like being Leonardo DiCaprio?".

Not surprisingly, DiCaprio has got the answer to that one pretty much sorted by now. But Ledoyen is still in her first few weeks of hearing it, so she answers it with quiet resignation. Like everyone, she pays tribute to Leo's skill and commitment as an actor. But the fame, she says, gets in the way.

Well, what she actually says is: "He's such a superstar and he has so much exposure and blah-blah-blah..."

On Saturday, you could have cut, sliced and wrapped the blah-blah-blah by the kilo. Sliced it, wrapped it and sold it outside on the street. Blah-blah-blah is, after all, the stock-in-trade of the film industry. Stardom is distilled blah-blah-blah. And Leonardo DiCaprio is 120% proof. This stuff is addictive and seductive and destructive. And self-generating.

Riding back from the Kempinski on the U-Bahn, I find myself thinking, "I bet that guy over there doesn't know I just talked to Leonardo DiCaprio!" That's a shaming thought for one of my years, but it did at least bring home to me what it must be like actually to be Leonardo DiCaprio from Christmas to breakfast time.

Leo's answer to the standard question about being him comes in various forms, the most direct of which goes something like this.

"Sure, it's definitely affected my life. The fine line that you try to walk is to somehow have a normal life and do things that you would normally do and at the same time be respectful of who you are. I try as much as I can to separate myself from that sort of image of me and try and maintain a normal existence on my own. I think that's the only healthy way to do it.

"The important thing from me is also not to disconnect myself from normal experiences and to go on doing real things and interacting with people just because of who I am. I don't believe that becoming a hermit is at all a sane or a logical way to deal with it."

Later in the day, someone tells me a story about how his daughter went to grade school with Leo in Los Angeles and remembers him standing at a bus stop on Pico, doing cigarette tricks for the girls in his class. Then, a year or so ago, the same daughter goes into a club on Sunset and there is Leo at the bar, doing cigarette tricks for the girls.

I'm not sure why I'm being told this story, but I laugh, in the way you laugh at stories about movie stars, because the point is usually that they are all air-heads. I've been thinking about this story, though, and I realise it is actually saying something else ­ something much more in Leo's favour.

And anyway, I prefer his own story. "I have vivid memories that are so closely attached to my childhood from coming to Germany," he says (his mother and maternal grandparents are German). "I remember entering a break-dancing competition here. I wasn't the best break-dancer, but they knew I was from the United States, so they gave me a trophy! I actually had a little USA tee-shirt that I wore around so anyone who wasn't actually clear would know where I was from. I was treated as 'the kid from Hollywood'."

It's only in transcribing this that I realise that, in the context of Berlin 2000, this story is positively dripping with irony. He's still the kid from Hollywood: but the tee-shirt has become him.

The questions that keep occurring to me as I write this are: What did we want him to do? Did we want him to turn down Titanic? And, having made it, was he supposed to want it to fail? It's not his fault that it's the biggest hit in the history of the cinema. How did we want him to act differently when it was? To denigrate the movie? To denigrate his performance?