When the Director reveals himself and his Agency's involvement in the murder to Lt. Columbo, he shows a card identifying himself as "Phil Corrigan, Secret Agent X-9," which is actually the title of a vintage newspaper comic strip and the name of its hero, created by
Dashiell Hammett, and filmed twice by the studio responsible for these "Columbo" telefilms, Universal, as a Saturday matinee cliffhanger serial, in 1937 and 1945, although the first time they changed the character's name to "Dexter".
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