The opening was a real nail-biter. The tension is already heavy as it begins, and it quickly piles up even more. The reactions of Nelson and the others, as they listen in helpless horror to the breakdown of the Polidor's crew, was very well done. I also liked Nelson's reaction a short time later, when he's ordering the Seaview to be prepped for the mission and is reminded that one of the crew that he mentioned by name had been on the Polidor.
I was rather startled when they showed the film clip of the "fear experiment" with the cat--because we have an old "Time-Life" book about the mind at home that shows still photographs of this very experiment, although I can't recall what they actually used as a fear stimulus.
Lloyd Bochner always makes a splendid villain, doesn't he? Slyly boosting the crew's fears while supposedly studying them. And I loved how quickly he came unglued when it turned out that there really was something to be frightened about.
It was interesting to see the different reactions of the men. Most of the crew were frightened on their own account, of course. Crane, whose primary concern is the safety of his ship and crew, was frightened on their behalf as well as his own. Nelson, on the other hand, was more frightened of failure than anything else, and therefore, his fears drove him to continue the mission rather than run from it. When Davis realized that the fear gas was turning into a lethal nerve gas, and rushed to confess to Nelson, Nelson's first concern was not the possibility of them all dying. He wanted to know if that fear gas had also been used on the Polidor. Learning that the Polidor's destruction had not been the result of natural panic, he quickly set his mind to finding a solution to the gas problem.
Aside from an initial outburst by one man, the crew got themselves under control pretty quickly (they've got good men on the Seaview), and quietly waited for the damaged ship to be repaired. We don't see anything of Davis at this point in the show--he's presumably in the brig--but I'll bet he was climbing the walls.
Quite an extraordinary show for so early in the series.