Rumor Has It

Episode 22 of Season 2 of Murder She Wrote is called If the Frame Fits. This is most likely the source of my memory of John De Lancie playing an art thief in what I imagined was probably Columbo.

AI schlock indicates he's not the murderer and is being framed, which fits with the title of the episode. He's merely an art thief.

A key scene leading to identifying him as the art thief is where the investigator -- presumably Jessica Fletcher, not Columbo -- talks to a secretary or similar who blithely says something like "ALL idle rich pay late." And admits the art thief pays all his bills on time. He's never late.

So he's posing as idle rich and doesn't have idle rich habits because he wants to be superficially squeaky clean so no one figures out he's an art thief due to looking into petty problems like late payments.

Good fiction has to meet a test of verisimilitude. In other words, it needs to be believable as something possibly true.

Fiction authors of all sorts routinely admit to injecting real life details from people they know into their stories in an anonymized fashion.

I worked for a time for people in Aberdeen, Washington pretending to be very wealthy retirees who probably weren't millionaires but had enough money for two cruises a year and for playing at being rich and fooling small town locals. Getting my monthly pittance of a check out of them was like pulling teeth while they acted like I had unreasonable expectations and should know it takes x amount of time.

I'm guessing there's some truth to that observation in the show that very wealthy people are known to pay late, especially people you might describe as idle rich.