This storyline will later resurface in The Jade Trap (1978), albeit with a heavily reworked script. That series often copied other shows. Virginia Gregg herself would end up appearing in their Of Ghosts and Angels (1980).
Recurring Dragnet actress, Virginia Gregg, plays the Jade collector who has been burglarized.
Bill tells Joe about his trip to Lancaster to test one of his homing pigeons. He describes the bird as heading straight up and then turning due West. In other episodes, it is established that Gannon lives in Eagle Rock which is south of Lancaster.
The number on the phone in the squad room where Joe and Bill sit is shown as 213-626-4421. As of 2022, that number is that of the U.S. Department of Justice.