Leading up to A Conversation with Mystery Writer Sharon Fiffer on October 2nd, we're presenting a festival of films based on the writings of Agatha Christie, the Queen of Suspense. This week, stop in for Witness for the Prosecution. Following a heart attack, barrister Wilfrid Robarts takes on the case of a struggling inventor accused of murder. Directed by Billy Wilder. Starring Tyrone Power, Marlene Dietrich, and Charles Laughton.