AceShowbiz - A movie starring Hayden Panettiere as convicted murderer Amanda Knox has been thrown into jeopardy after lawyers for the jailed American student vowed to challenge plans to turn her story into a film.

Executives at America's Lifetime network announced this week that the "Heroes" actress has signed up to appear in "The Amanda Knox Story", based on the 21 year old's sensational Italian murder trial over the brutal killing of her roommate. Meredith Kercher was killed during a violent night fueled by sex and drugs in 2007 and last year Knox was sentenced to 26 years in prison for slashing her friend's throat with a knife.

Knox has maintained her innocence and is challenging the guilty verdict - and her lawyers are adamant movie bosses should not be allowed to take her story to Hollywood until the outcome of the appeal is heard. Knox's attorney Maria Del Grosso, says, "It is inconceivable to make a film when a final verdict on this case has not been reached."

Giulia Bongiorno, a lawyer representing Knox's ex-boyfriend Raffaele Sollecito, who was also convicted of Kercher's murder, adds, "If the film is shown before the end of the appeals trial we will request it be seized (by authorities)." Both their appeals are to go to court later this year.