Kitty Kelley, a biographer known for dishing dirt on celebrities, has selected her next subject — Oprah Winfrey.

Author Kitty Kelley during an interview with the Associated Press in 1997.
(Marty Lederhandler/ Associated Press)

"Oprah Winfrey has fascinated me for many years — as a woman, she has wielded an unprecedented amount of influence over the American culture and psyche," Kelley said in a statement Wednesday.

Kelley is the author of tell-all, unauthorized biographies of famous people including Frank Sinatra, Nancy Reagan and the Bush family.

In Reagan's biography, called "encyclopedically vicious" by the New York Times, she hinted Sinatra and Reagan may have had an affair while she was first lady.

In her book on the Bush clan, The Family: The Real Story of the Bush Dynasty, she alleged George W. Bush brought cocaine to Camp David while his father was president, a charge later denied by the supposed source.

Crown Publishing Group, part of Random House, will publish the Winfrey biography, which does not yet have a title.

To write about Winfrey, Kelley "plans to interview hundreds of sources, many of whom have never before spoken on the record about her subject," Crown said in a statement.

Called the "colonoscopist to the stars" by satirical magazine Slate, Kelley is said to have sent her husband out on daily trawls through celebrities' garbage cans to dig up information.

She first gained notoriety with Jackie Oh!, a 1978 bio of Jacqueline Onassis that uncovered U.S. President John F. Kennedy's infidelity.

She also wrote the 1997 book The Royals, which was never released in the U.K. because of fear of libel suits.

Oprah Winfrey, shown in November 2006 in New York, has 'fascinated' celebrity biographer Kitty Kelley for years.
(Dima Gavrysh/ Associated Press)

Kelley appears to admire the daytalk show host, who is followed by 30 million U.S. viewers a week.

"She has built an empire around her personality and has been one of America's most admired business women and philanthropists," Kelley said in her statement.

"Oprah's story is one of hope, promise and realization of the American dream."