I agree with the last reviewer, Robert Loggia plays it over the top here, but there is an explanation.
Answer: director Michael Caffey. At the time, Caffey was also directing BARNABY JONES, who had his fair share of hot heads and nut cases, also he directed a long line of cop shows. This was his cup of tea. Additionally, Leonard Kantor wrote the story, who began his career with THE UNTOUCHABLES, with lots of angry gangsta's. Do the math.
Loggia plays Johnny, a mob boss (with a short fuse) who hires Cannon to figure out who put a hit on his former wife --or was it for him? Very similar to a MANNIX story because Joe often had a clients who never fessed up. Why not tell the truth???
More over, everyone in the "family" seems to have an attitude problem. Now that's fun for Cannon. Best of the best is Madlyn Rhue, playing Phyllis, Loggia's ex wife. Rhue also was no stranger to cop shows, and worked with her old boss, William Conrad, at Warner Brothers/ABC. She was everywhere on tv, and for good reason. She was one actress who should have written a book on acting.
David Opatoshu plays Lucius and Harry Rhodes represents the police. Notes indicate this was the last appearance of Bob Harks (this time playing a murder victim???). Harks held a record for appearing in hundreds of tv shows, mostly bit roles. His face you recognize, but not his name.
By the way, it's long gone, but we get to see some great shots of the legendary Pike Amusement Park in Long Beach. This was "the" place to have fun back in the day, replete with attractions and rides before it was razed and sold to land developers.
A top episode with late night tea! Also for all us fans of Madlyn Rhue. SEASON 5 EPISODE 22 remastered (2016) CBS dvd box set.