It’s a multi-million dollar secret kept under wraps every year.  Six undisclosed locations, eighteen bikini-clad models and a quarter of a million images to choose from, but when the 2010 Sports Illustrated Swimsuit Issue is finally revealed, it will be a global sensation like no other.

On Tuesday, February 9th at 9PM ET/PT, CNBC presents “Business Model: Inside the Sports Illustrated Swimsuit Issue,” a CNBC Original reported by CNBC’s Sports Business Reporter Darren Rovell that takes an unprecedented look inside the most profitable single-issue magazine in the world.  In a television exclusive, CNBC, First in Business Worldwide, reveals how business, beauty, fashion and sports come together to create this much-anticipated, multi-dimensional franchise that alone generated 7 percent of Time Inc. News Group’s annual revenue in 2009.

The Sports Illustrated Swimsuit Issue means big business not only for Time Inc., but also for the models, advertisers, fashion designers and locations that grace its pages. Rovell gives viewers a behind-the-scenes look at the scouting, set-up and inner-workings of the photo shoots as he travels to one of the exquisite undisclosed locations and interviews models, each vying for the ultimate prize—being featured on the cover of this year’s issue and becoming a household name.

The one-hour documentary looks at the history and unparalleled success of the Sports Illustrated Swimsuit Issue, which continues to print its own profits even amid an economic downturn and a troubled period for the publishing industry.  The issue, which started in 1964 as a five-page supplement each February to heat up the winter months, has become over the years a billion dollar multi-platform empire that Fortune 500 companies clamor to be associated with. Rovell interviews executives with Miller Lite and Pepsi about being part of what’s been dubbed “the print Super Bowl of advertising.”

CNBC also catches up with former Sports Illustrated Swimsuit supermodels Cheryl Tiegs, Carol Alt and Kathy Ireland. The Swimsuit issue opened doors for Ireland and now she talks to CNBC about her marketing and design company, Kathy Ireland Worldwide (KIWW), which does 1.4 billion dollars in annual sales.