The sensational story of American student Amanda Knox -- serving a 26-year prison term in Italy for murder -- comes to U.S. television next month, but the actress playing her says she still has no idea whether Knox is guilty or innocent.

"It is one of those stories, which is really riveting but where you just don't know. We spent five weeks just talking about it and reading about it, and trying to form some opinion," actress Hayden Panettiere said on Friday.

"I can't say I have an opinion (about her guilt or innocence). I don't know that we will ever really know," Panettiere told U.S. television writers.

"Amanda Knox: Murder on Trial in Italy" recreates the life of the student dubbed "Foxy Knoxy" by the media, who was convicted of murdering British roommate Meredith Kercher, in the Italian town of Perugia in 2007 in what Italian prosecutors alleged was a frenzied sex game that spiraled out of control.

The dramatized story of the events leading up to the murder will be broadcast on the Lifetime network on February 21.

An Italian court is currently hearing Knox's appeal of her conviction. The half-naked body of Kercher, 21, was found locked in her blood-spattered bedroom with a stab wound to her throat in the house she shared with Knox and two other students.

Producers said they did not contact the families of either Knox, now 23, or Kercher, or Knox's Italian boyfriend Raffaele Sollecito, who was also convicted and jailed.

Instead they worked from detailed Italian court documents about the case, as well as media reports, many of which painted Knox as a promiscuous and calculating killer.

"We were very careful not to be partial in the way we told this story. We feel we have done this very responsibly," executive producer Trevor Walton said.

"We didn't want to be biased in any way. To go to the Knox family, and not to go to the Kercher family, didn't make any sense," he added.

Producers said they wanted to focus on the human drama and the relationship between Knox and her mother, rather than trying to establish guilt or innocence in the case that made headlines around the world.

"We are not detectives. We are filmmakers. We just wanted to tell a dramatic story, " said director Robert Dornhelm.

Filming took place in Rome, Perugia and Seattle in the autumn of 2010. Panettiere, 21, is best known for her role as a cheerleader in the NBC television series "Heroes" and for the movies "Raising Helen" and "I Love You Beth Cooper."