The filming location Piru, California, used here as Parker Junction, is used in several Barnaby Jones episodes as different small towns.
Loosely based upon the exploits of Dan Cooper, who hijacked a 727 aircraft in late November of 1971 (some 15 months before this episode was filmed). Cooper parachuted from that jet with a $200,000 cash ransom, somewhere between Portland and Seattle, and was never found.
Something that usually does not happen in this series happens here. A character says the title of the episode in the dialogue. Barnably uses the term 'Murder-Go-Round' and explains the meaning.
At the bait and tackle shop Barnaby tells the owner he used to run a place like this.