American Deborah Lipstadt brought a lawsuit against British historian David Irving in 1999. Though the case was based on libel grounds, it became a challenge to Irving's claims that the Holocaust never really occurred, and that Adolf Hitler never ordered the mass slaughter of millions of Jews and others deemed societal outcasts. A reenactment of court testimony brings this unusual trial to life. Viewers should be aware that the film contains graphic footage of offensive Nazi behavior. This program is a part of the Nova series that's regularly aired by PBS.