Tying up a loose end, Mannix explains his break with Intertect, the high-tech detective agency he worked for in the first season. In a conversation with the deaf actress Jody, Mannix says that he has always been a loner and that one day he got fed up and cursed at one of Wickersham's machines. When he thought he heard the machine curse back at him, he decided to quit. It isn't stated how long Mannix has been an independent private detective, although this story finds Mannix settled into a new office, driving a new car, and it is implied by the easy rapport that he and Peggy have been working together for some time.
This was Gail Fisher's first appearance as Mannix's secretary/girl Friday Peggy Fair and she would appear in this role until the series end.
At 18:30 the hired killer aims his rifle at Mannix using an infra-red telescopic sight. This distinctive rifle is a slightly modified Thrush Rifle which was frequently used on the previously canceled series The Man from U.N.C.L.E. (1964).
Audree Norton receives an "introducing" credit, referring to her a "of the National Theatre Of The Deaf".
The park where the phone call was made is a small park that is located about 100 yards down the street from where Mannix has his office. The same park will be seen and used many times, even when the location is another city or even another state.