“The Night Stalker” starring Darren McGavin was first televised on ABC as a TV movie in 1972. The film was based on the then-unpublished novel by Jeff Rice titled “The Kolchak Papers” (a.k.a. “The Kolchak Tapes”). From Wipekedia: Actor Darren McGavin recalled that his involvement began when “My representatives called to say that ABC had purchased the rights to a book called The Kolchak Papers. They were into a kind of first draft of a script by Richard Matheson, and they called the agency to ask them if I’d be interested in doing it. My representative read it and called me.” The popular TV movie, along with its sequel and the TV series, provided the inspiration for Chris Carter’s The X-Files.
“The Night Stalker” led to the weekly series “Kolchak: The Night Stalker” in 1974 but that only ran for one season. Yet, it remains a cult favorite and it provided the inspiration for “The X-Files” on Fox.