NEVADA — A plea change hearing is scheduled for later this month in Story County District Court for a Mason City man charged with extortion. 19-year-old Christian Gossweiler has already been sentenced in two cases of extortion in Black Hawk and Story counties where he was accused of threatening to post nude photos of women online unless they had sex with him. Gossweiler was scheduled to stand trial later this month in another Story County case where he targeted an Iowa State University student in 2018. Online court records show he filed a written plea of guilty in the case on Friday, with a formal plea change hearing scheduled for September 20th. Gossweiler was sentenced to five years in prison late last month on the Black Hawk County charge and was given probation in the first Story County case. A plea agreement in a Scott County case involving a UNI victim was rejected in June with a trial now scheduled to start on September 30th.