"Columbo's Progress." Or, "Tips For Junior G-Men."

I do not intend to detract from the stellar sleuthmanship of COLUMBO, not an iota. However, every crime he's ever solved with great subtlety and ingenuity could actually be solved in less time in a more banal manner. By a three day old child.

Every week, Columbo comes upon the murder scene to investigate, and while he is doing so, one person in particular with some connection to the deceased takes a particular, you might say peculiar, interest in Columbo's progress.

Men cluster to me like moths around a flame

But if their wings burn I know I'm not to blame.

The killers fall fatally into a protracted, although (absurdly) ostensibly casual, dialogue about the murder and how it was done. The killer always tries with pronounced vigour to discount each of Columbo's ideas, and to convince him that his hypotheses are wrong. They very reluctantly concede his point finally, and pull an obviously thwarted expression.

Why doesn't anyone ever have the good sense to shut up and act uninterested? Or don't talk to Columbo at all for fear of incriminating yourself with hubris? Go take a vacation. But they must stick around. They are drawn to Columbo. They must argue it.  The vanity of the assassin! The brass neck of the psychopath.

Columbo should by now be able to identify the killer as the person who invariably takes an inordinate interest in the progress of the case, who tries to argue over every conjecture with him, who soon gets "frustrated," now peeved, finally accuses him of harassment and threatens to call his superiors.

To all this, Columbo would sagely nod and remind me: you need motive you need proof and you need opportunity.