Cannon
Cain's Mark
TV Flash files “Cain's Mark” as hour 23 of 120 in the TV Flash guide — Cannon (1971–1976) on CBS, season 1, episode 23, aired 1972-03-07, 60 min.
From the desk
How this hour is filed
This leaf is S01E23: listed hour 23 of 120 in the Cannon guide, hour 23 of 24 in season 1. It aired 1972-03-07 (60 min). The listed hour before it is “The Torch” (S01E22). Next is “Murder by Moonlight” (S01E24).

Catalog log
Broadcast listing — not a TV Flash recap.
A mother hires Cannon to track down her wayward son before he misses his probation meeting.
Viewer FAQ
Where does Cain's Mark sit in the Cannon guide?
S01E23 is listed hour 23 of 120 — hour 23 of 24 in season 1, season 1 episode 23.
When did Cannon S01E23 air?
Cain's Mark aired 1972-03-07 and is listed at 60 minutes.
Is Cannon's size the joke?
No. Conrad's bulk is text, not a punchline. The series is a heavyweight PI who never auditioned as a pretty leading man and did not need to.
In the series
Why this series still plays
William Conrad's Frank Cannon is the heavyweight detective who never auditioned as a leading man and did not need to. Radio's Gunsmoke marshal finds a new generation via Lincoln Continentals and stubborn casework. A Quinn Martin mystery that stars a voice, a bulk, and zero apology.
So the group chat wants a pretty-boy PI in a tuxedo (Lana would call it a *gown of authority*) and then Cannon rolls up in a Lincoln Continental like that was the whole look. CBS, 1971–1976: William Conrad's Frank Cannon is overweight, expensive, and brilliant, and Edward Hume and Quinn Martin put him at the center of the early-1970s detective boom without asking him to audition as a leading man. Radio's Gunsmoke marshal found a new generation via stubborn casework and gourmet side trips. (I said spoiler-free.…
Filed against
- William Conrad as Frank Cannon
William Conrad’s Frank Cannon never auditioned as a leading man and did not need to — heavyweight detective, Lincoln Continentals, stubborn casework, a Quinn Martin mystery that stars a voice, a bulk, and zero apology. Radio muscle…