This is really covering very old ground, but...

There are some clear plot holes in this episode. However, we're not told when Carsini's brother actually died. It might have taken a while to suffocate (if it were plausible to do so) in a room of that size. Based on the discussion of the 'empty stomach', there's some indication that it took a little while. Carsini's reaction when switching the air conditioner back on gives the impression that the air is somewhat stale.

We're asked to believe that under no circumstances would Carsini have allowed the wine to be spoiled except for something as important as covering up a murder. The point is, when Columbo finds out, it's enough to make Carsini confess.

The apology, whether authentic or not, is Columbo's way of setting up the restaurant scene.

I do remember seeing Adrian look up at the ceiling as he returns to the body in the vault, possibly as if he's been overcome by a bad smell? Well, no, probably not... But this also reminds me of Try And Catch Me, where the nephew dies after just one night (did I remember that right?) in Abigail Mitchell's safe, with the killer jetting off to New York once again. Surely a man could survive for longer than that without food or water?

One more question. If the wine cellar door opened so easily from the inside (as Adrian demonstrated to Columbo), why couldn't the brother just have left when he woke up? It looked like only his wrists were tied together, not that he was strapped or chained to anything. What am I missing here?

Old ground indeed.

This could very well be old ground but obviously people are interested. There are also new forum reader who are curious about topics that have been covered but do not have the time to search the entire forum. I imagine that those who do not like going over covered ground can start new threads.

Gee, thanks for straightening the obvious out, but anyone with half a piece of working brain can research the answers without rehashing the same tired old topical material here. I mean, come on, do you you actually believe that these queries are posted by NEW contributors to this forum? If you do, then you're thought process is as limited as the global interest in this topic.