Her books have generated endless controversy as they have dug deep into the lives of global icons, such as Jackie Onassis, Frank Sinatra and the British royal family.

But they have also made her an internationally best-selling author.

Few have managed to carve out such a successful career by delving so thoroughly into the lives of the rich and famous. But Kitty Kelley found that the public's appetite for the untold stories about the stars is endless.

Her career began in the 1960s once she moved to Washington DC to work as a press assistant for the influential US senator, Eugene McCarthy.

Kelley then took a more journalistic path ending up at the Washington Post, but found that she got more traction from articles looking behind the scenes at the lives of celebrities.

Kelley is acknowledged as someone who spends years researching her subjects, but she also remains controversial for some of the content she includes in her books, which is perhaps, why she continues to be such a best-selling author.

This episode of One on One aired from Saturday, January 1, 2011.