I've haven't posted here for years but I used to be the member 'Son Of A Gun'. Please find a YouTube link posted below where you can watch Bert Freed as Columbo in Enough Rope (1960), which is an earlier version of what would become the standalone first episode Prescription: Murder (1968), starring peter Falk as Columbo:
Thanks for the suggestion. I'll take a look at that thread.
I thought there would have been more interest in this find but I gather that The Lt. Columbo Forum is sadly quieter these days. I had assumed that not many people would have seen it.
You're right, I for example watched all 69 columbo episodes, some several times, and never watched this earlier version of the first episode, guessing I should when I have some time.