Expanding on my Phillip Marlowe list, this is a list of films with a private detective as the central character. See the notes to see details on P.I. names and book authors from which the movies are derived. Suggestions are always welcome.
Not in the database:
a 1977 NBC Movie of the Week called Stonestreet: Who Killed the Centerfold Model? starring Barbara Eden.
Also "Fly Paper" The Continental Op by Dashiell Hammett. Stars Christopher Lloyd. This is episode five of season two of "Fallen Angels." It was directed by Tim Hunter from a teleplay by Donald E. Westlake. youtu.be/w8G5cuTNlD0
Also Gumshoe! (2018) director Michael Webb on Amazon Prime looks to be a goofy spoof.