COULD a casual, gung-ho documentary maker, most famous for eating a month's worth of McDonald's meals, really track down the world's most wanted man?

Unlikely as it may seem, Morgan Spurlock, in his inimitable style, sets out to do exactly that in his new documentary film, Where In The World Is Osama Bin Laden?

Luckily Morgan, who gained 25lbs eating a diet consisting solely of McDonald's burgers for his Oscar-nominated documentary Supersize Me, doesn't shy away from a challenge.

Which is just as well, when you consider the politically volatile countries - Saudi Arabia, Afghanistan, Pakistan and Israel - which were on his hit list.

"When I make a movie, I'm not saying I'm going to go out and change the world," says Morgan. "With Supersize Me, it was a great way to deal with a serious issue.

"I thought the same thing about this film. This is a great way to deal with this kind of world we live in. To question the war on terror, ask what creates an Osama Bin Laden to begin with, and to go on a fun journey."

What makes this journey all the more poignant is the fact that he had to leave his wife Alex at home in New York, pregnant with their first child.

"It changes the way we think about things," Morgan reveals. "What really hit me is, what kind of world am I about to bring my kid into? So, me starting the journey with my wife being pregnant, I thought was a great piece. I'm a big believer in a personal journey."

But with the knowledge that he was about to become a dad, Morgan had to make the tough decision whether he could go through with the project at all.

"Alex and I talked about not doing the movie," he admits. "But it felt like an important thing that I had to do. So, as much as my wife didn't want me to do it, she went along with it. She just said, Be back.' "I also promised her that we wouldn't go to Iraq because the Iraq war was in full bloom, as it still is," he adds. "But I personally never really wanted to go there. We've heard that story and we see it every day on the news. I felt Afghanistan was much better to link to Osama Bin Laden, to the journey and to make it all fit."

Clearly the film isn't just about the search for Bin Laden. It explores deeper issues, with Morgan discovering that Middle Eastern attitudes towards Americans aren't always that bad, experiencing what it's like for an ordinary family living in war-torn Afghanistan, and trying to glean just what censored Saudi Arabian students are really thinking.

"You start to get the sense that it's not about Osama," says Morgan. "People have come up to me and said, I never see the people that you spoke to in this movie on TV.' For me, if this film presents a view of the moderates we never get to hear from, in a favourable light, then maybe things could start to change."

To prepare for his foray into war-torn and volatile territories, Morgan underwent hostile environment training with former SAS men, which helped mentally and physically prepare him for the unexpected.

"When a mortar is fired in front of you, where's the best place to go? If somebody's shot in the arm, how do you deal with that? It's knowing what to do when these things happen."

For protection, Morgan was accompanied by a security advisor who was on hand to tell the crew when they should leave.

"We'd be on the ground and he'd say, We need to get the car and go.' We left a driver in the car all the time, so there would be no chance of somebody planting a bomb on the car.

"There's a tremendous amount of fear that comes with being in an area like that, but you just have to keep going."

He admits being genuinely scared at times. "When I was embedded with the military in Afghanistan, it was incredibly frightening," he says. "You do feel safe and protected because you are surrounded by guys with guns, but at the same time, these guys are targets. They all have weapons in case something goes bad, but that's not going to stop an IED (Improvised Explosive Device).

"When we were going on our convoy, we got diverted because they had spotted an IED, halfway up our road. The bomb squad had to go and diffuse it. There was a Taliban ambush and the operating base we were staying on had a rocket attack the week before we got there, so you never know. Those guys are putting their lives on the line every day."

The finished film not only sees some comic moments, like a cartoon of Osama Bin Laden dancing to MC Hammer's U Can't Touch This, but provides simple information and statistics on American foreign policy.

"If this film stirs up a foreign policy debate, and how we deal with people who are threats to our country, that would be great," says Morgan, who adds that he tried to steer away from letting his personal politics into in the movie.

"Most Americans are frustrated and upset with the direction which our country is going and I'm part of that majority," he says.

"I could have easily jumped on a Bush bash' train in this movie and said, It's his fault.' But we need to start looking ahead. Someone else is going to get elected. What are they going to do? How do we want to see ourselves in the world? How do we want others to see us?"

So after a seven-month quest and hundreds of hours of film, did Morgan get any closer to discovering where Osama really is?

"You realise he is like Keyser Soze from the film The Usual Suspects," he chuckles. "He's everywhere and he's nowhere."

What next for Morgan? Will he continue to put his physical self on the line in the name of film-making?

"My wife Alex tells me no, I'm not," he says ruefully. "She's says that I've got to make a movie about flowers or fish or something."