Seconds after meeting Entourage’s Adrian Grenier (just as charismatic in person, and taller than I’d imagined), he tells me he has to zip to the washroom. I try to escape to the other end of the swank Thompson Hotel suite, but can’t avoid hearing the tinkle, flush and (I listen for it) tap. “So even celebrities have to go to the washroom, huh?” I ask when he emerges. “Yup,” he smiles. “We need to drain the weasel.”

Deconstructing celebrity culture – particularly the “paps” who hound the rich and famous – is what his doc, Teenage Paparazzo’s, all about. Grenier follows the life of Austin Visschedyk, a mop-haired shooter who begins photographing him, only to become semi-famous himself.

Has making the film changed your relationship to the “paps”?
Absolutely. Gaining that perspective is very empowering. Dealing with them is now more of a two-way conversation.

Was there a flashbulb moment when you realized you wanted to make a movie about paparazzi?
It was meeting Austin. Our stars were aligned – pun intended. I was looking to do something, had read the book Mediated, which primed my thinking about the subject. Everything led up to this moment. Then I saw this kid taking photos. Boom.

You got interviews with Paris Hilton and Lindsay Lohan. Would an unknown have had the same access?
Probably not, and it would have been a completely different film. Perhaps if it had been a famous filmmaker…. I was in a unique place. I had an opportunity to gain access to certain celebrities but also tell the story from a certain point of view and a willingness to exploit that point of view.

At one point you walk around with friend Paris Hilton to see if the tabloids will make up a story about the two of you. Was that surreal?
I relished it. It was a “Ha ha! We got you” moment. I knew that would be part of the movie. But it wasn’t new to me. I’d experienced [them twisting the truth] before.

Do you keep in touch with Austin?
Yeah, it sort of evolved into a different kind of relationship. It’s no longer this paparazzo/celebrity relationship, but more like a friendship, brotherhood, mentorship.

Is he still in the business?
He better not be or I’ll whup his ass. No, he can make his own choices. This is a coming-of-age story. At a certain point he’s got to be his own man.

Favourite doc filmmakers?
Herzog. I wanted to be Herzog in my movie. I loved the philosophical and poetic nature of his narration in Grizzly Man. But what I realized was that my voice can’t be Herzog’s. As much as I fantasize about being a poet, I had to also find my more humble self. Eva Longoria says, “Nobody wants to see a celebrity complain.” They also don’t want to see a celebrity acting all poetic.

There are rumours about Entourage ending. Is it time?
I think we’re going to end in the perfect way, but it’s not quite over. We’ve got a couple more years.

Vinnie dated a porn star this season. Would you ever date one in real life?
If I fell in love with her, sure.

Maury Chaykin, who played a character loosely based on Harvey Weinstein in Entourage, passed away recently. Any memories?
He was such a fun guy, and so exaggerated. Absolutely lovely to watch.

Are you scared of being so associated with your Entourage role that people might not believe you in anything else?
I can always just direct. I love documentaries. I have at least one more in me.