LOS ANGELES — “When I talk to you, it does not necessarily mean that I have to like you,” Werner Herzog, off-camera, can be heard telling the death-row inmate Michael Perry in the opening minutes of “Into the Abyss,” a new documentary about Mr. Perry’s execution in Texas last year for the murder of a 50-year-old nurse, Sandra Stotler.

“But I respect you, and you are a human being, and I do not think human beings should be executed.”

With that, Mr. Herzog begins to ask questions of Mr. Perry and those who had a stake in his life and death: Was it drugs? You had hopes? Why did the victims die?

It is a reporter’s drill, apparently designed less to resolve lingering questions about the crime — and the shotgun slaying on the same night of Ms. Stotler’s 16-year-old son and his friend — than to test Mr. Herzog’s antipathy toward the death penalty against a close encounter with murder and its consequences.

Speaking by telephone on Saturday, minutes after introducing “Into the Abyss” at the Telluride Film Festival in Colorado, Mr. Herzog said, “I am not in the business of guilt or innocence.” The screening of his film marked the beginning of what promises to be a rich season for documentaries. On Thursday Mr. Herzog and his movie will be in Canada for the Toronto International Film Festival, where the reality-film genre will pass a milestone. For the first time in the Toronto festival’s 36-year history, a documentary, Davis Guggenheim’s “From the Sky Down,” about the band U2, will be featured at the opening-night gala on Thursday evening.