My vote for worst episode is "Mind over Mayhem" with
the robot. It was like they made this episode
for a Saturday morning kiddie cartoon version of
Columbo--a real disgrace.

"Agenda for Murder" is one of the few episodes
of the revival of Columbo that I have seen and
I didn't care for it. It didn't make much of
an impression on me and I thought the bit about
the teeth marks was not impressive.

Although I have great respect for McGoohan as
an actor, the final episode of "The Prisoner"
which he was forced to write when the originator
of the series, George Markstein, quit in a huff
without telling anyone how he intended to wrap
it up,
is considered to be a disaster by many, maybe
most of the fans of the series. It is hallucinatory,
violent, uncoordinated and just downright bizarre.
McGoohan in best in front of the camera.

Oh now I remember you saying that in the past about Mayhem. I remember you saying that bit about it looking and feeling like a Saturday Morning kid's show....and I recall the first time you said that I sat there thinking how right you were. It was a thought which had never occured to me, but you hit it on the head.
And I agree, not a very good episode at all. This is one episode which makes me feel quite claustrophobic. All the scenes in the dreary think tank....there is no panache, no beautiful mansions....and also no chemistry between the murderer and Columbo.