Hi, I think it needs to be noted that there could be a reason why this particular episode is so shoddy (my apologies to those who've enjoyed it, but my feeling is that this one is bobbins). If memory serves me correctly, it was directed by Patrick Macgoohan, and he has been known to take liberties with scripts. He directed the final episode of The Prisoner with the same callous disregard for the form, style and substance of that series, and methinks he did the same with Columbo.
Or maybe not; that's my excuse anyway.
Incidentally for our non-English Columbophile friends, bobbins=rubbish.
Ta ra,
Sita xx