Exclusive ENQUIRER blockbuster investigation:  Oprah smoked crack cocaine during a sexually charged affair, according to her dying ex-love …  and the shocking relapse came years after her first flirtation with drugs!

Oprah confessed to her audience she briefly used cocaine in the 1970s. At the time she blamed it on her desperate obsession with a man who was a drug user.

But in his blockbuster sex-and-drug tell-all The Wizard of O: My Life With Oprah, her ex-lover, Chicago businessman Randolph Cook, makes the stunning disclosure that the talk queen resumed her cocaine habit during their secret affair which began in 1984.  Cook, 51, also claims the media mogul taught him how to smoke crack cocaine, and the two "freebased" the drug regularly during their passionate six-month romance and the talk show titan  "was still under the influence while doing her show."

Cook recently has been diagnosed with esophageal cancer and with only two years to live he blames Oprah for his problems and wants his story told. And court papers back up Cook’s shocking drug allegations about Oprah!

During an ENQUIRER investigation in 2007, reporters unearthed a secret 17-page court document in store rooms at Chicago’s National Archives and Records Administration that support Cook’s shocking drug claims.

The document, titled "Defendant Oprah Winfrey’s Answer to Plaintiff’s Amended Complaint At Law," reveals: "Defendant admits that she and Cook had sexual relations." And it also says: "Defendant admits that Cook used cocaine in her presence and that she used cocaine while Cook was present."

 "Americans have placed Oprah on a pedestal that has been seemingly invincible until now," Cook writes.

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