An unsold TV pilot from 1963 called "The Plot Thickens". Same concept as the early 1950s series "Crawford Mystery Theatre" (of which only a single kinescope survives...anyone able to upload it?). In this pilot, a panel is shown a short film about a crime, and then has to guess who the guilty person is. Features Groucho Marx as one of the panel members. Could someone please check that this is public domain?