"Big Brother" huge worldwide, not just in U.S.

"Big Brother" kicks-off its 13th season tonight.

If you're a fan, you know the reality show is a cutthroat competition for half-a-million dollars. But what you might NOT know is that "Big Brother" is a GLOBAL phenomenon.

And, reports National Correspondent Ben Tracy, it's a much different game in dozens of countries world-wide.

Variations of the show have been international hits since 1999, ranking near the top of the ratings in almost every country in which they air, with millions of voyeuristic viewers.

"Right now," says Variety TV Editor Andrew Wallenstein, " 'Big Brother' is in 81 countries, with 19 different versions at last count. So, when you're talking 'global phenomenon,' it doesn't get any bigger than that."

One contestant, in the Israeli version said, in Hebrew, 'I like to win. I'm a winner. I like to go all the way and succeed."

Every edition of "Big Brother" follows the same basic game-plan: A houseful of strangers with diverse personalities, pulled from the entire spectrum of society, are locked away from the outside world for months on end. The volatile mix guarantees a season of tears, trials, and triumphs.

Week by week, houseguests are eliminated until only one winner remains, taking home between $100,000 and $500,000.

"In the very early stages of brainstorming about 'Big Brother,"' says Iris Boelhouwer, Managing Director of Creative Operations of production company Endemol, "we often had the discussion, 'How interesting can it be to put 10 people in a house and just watch what they're doing?' And in the end, it turned out to be a major success and very compelling to watch people."

Eleven years ago, "Big Brother" 's first U.S. season followed the international model. But the format that worked everywhere else didn't work in America.

Host Julie Chen recalls, "When we first started the show, we did it by the book. Which is, we had America vote on who they wanted to stay in and who they wanted to kick out. And I found out that Americans, we don't like conflict. Americans voted out the most interesting players in the game!"

Says Allison Grodner "Big Brother" Exec. Producer Allison Grodner, "It was put to us ultimately to decide, 'Well, how do we make this interesting for an American audience?' And we really had to take the power of the weekly vote out of the viewer's hands in order to do that."

So, in the U.S., the houseguests themselves vote to determine who will win.

But that's not the only difference between the U.S. and foreign versions of "Big Brother."

Variety's Wallenstein says, "The funny thing about the foreign versions is, it's almost like a game-within-a-game to watch. 'Well, how soon will it be before two contestants jump into bed with each other?' And I think it's kinda part of the show's appeal, whether you're in Europe or Africa."

"it took us four years of this show until we had sex in the 'Big Brother' house," Chen says, "because we are more conservative as Americans. Not that I'm saying there SHOULD be sex in the 'Big Brother' house, but I will say that, in the U,K,, in the Netherlands, in Italy, strangers were having sex, like three days in!"

Ultimately though, the show's creators say "Big Brother" 's international success goes beyond mere "sex appeal."

"It's not about swearing, says Endemol's Boelhouwer, "and it's not about nudity, and it's not about sex. It's about all the relationships inside the house."

And, concludes Tracy, it's safe to say, the whole world is watching.