CBS television will broadcast a special report about the Amanda Knox case that includes a letter written by the American student while behind bars for murder in Italy, as well as video diaries made by her best friend.

CBS said on Thursday that Amanda Knox: The Untold Story will air on Saturday. The network said the program would reveal the cruel manipulation and sexual intimidation Amanda endured while behind bars, in her own words, from a letter that she wrote.

Knox, 24, was freed from four years in an Italian prison on Monday after an appeals court overturned her conviction for murdering British housemate Meredith Kercher in 2007 in what prosecutors alleged was a drug-fueled sexual assault.

She made a tearful return on Wednesday to her home city Seattle, where she has largely been seen as an innocent girl trapped abroad in an archaic justice system.

The CBS program is based on a report by its correspondent Peter Van Sant, who covered the Knox case both in the Italian hill town Perugia and followed her home to Seattle.

It includes details of a letter that Knox wrote from prison to investigative journalist Bob Graham, in which she says that an Italian prison administrator ordered her into his office alone late at night to talk about sex.

The program said Knox came to believe that the motive for the encounter was to provoke her into saying something that would support the prosecution theory that she was a sex-crazed killer.

Knox will not be appearing herself.

The show will also broadcast video diaries made by Knox's best friend Madison Paxton, who moved to Italy to help Knox fight for her freedom.

Knox has remained out of the public eye since her return to the United States, despite rampant speculation that she had signed deals to appear immediately on U.S. television shows to tell her story. Publishers are also approaching Knox for a book deal.

The CBS program is thought to be the first in a slew of such TV shows about the Knox case. A Lifetime television movie starring Hayden Panettiere, called Amanda Knox: Murder on Trial in Italy, which was first broadcast without the Knox family's cooperation in February, was repeated several times this week after news broke that she had been freed.

Court