Oh...I forgot....Thanks to Mark Dawidziak and his wonderful Columbo Phile for helping me through that.....it is almost 11:00 pm here....so the brain is getting a bit thick!!!

Break this one down to three main timing inconsistencies:

1. Eddie Kane could not have used the key left on the floor because Mallory had changed the lock.

2. The key on Kane's key ring was for the lock that had
been changed yet again, this time at Columbo's direction.

3. The manuscript written "nine months ago" involved an ending invented just a week ago.

Well!!!....Mr. David!! Where were you when I was languishing in describing the plot??? I could have used you then. I went into this whole long thing, and you come up with such a simple, but concise reply! Thanks!