I need to file an "au contraire" reaction to this episde -I was a "Cannon" fan back watching it in first-run, not the least of which because of the dependable performing of character actor William Conrad, but this hour was strictly dullsville.
Guet talent is boring as is the story, with a particularly annoying musical score that Mickey Mouse each suspense or actin scene in as distracting a fashion as possible. At one point the awful music blaring reminded me of the "Batman" series, but in this case it wasn't supposed to be funny.
I did not see this episode when it was aired in 1971, but waiting all these years only worked against it, that is unless you are inclined to shill for a show.