Kirk and the derelict starship Defiant vanish into a spatial interphase between universes. To rescue him, Spock must maintain position despite a growing, violent hysteria aboard the Enterprise, like that which destroyed the Defiant's crew, as well as a force field being laid around the Enterprise by Tholian patrol ships. Written by
Did You Know?
First episode to show the environmental suit. Something that was avoided before not only because of the cost but of the problems of the suit having to have a helmet with a clear window. Such a window would always pick up unwanted reflections and make recording the actor's lines difficult. Since these outfits were only meant to be seen only in NTSC resolution, someone came up with the ingenious solution of making the "window" out of mesh. Mesh would provide the diffusion to make it seem there was something clear and solid in front of the actor's face and reflections and recording dialog would be no problem. The way the shows were broadcast back then it would provide successful illusion of a solid face plate for the most part. It was not until DVD, which achieved the highest quality of NTSC resolution that the use of mesh became much more noticeable. And now, with high definition resolution, you can see the texture and wrinkling if the mesh quite easily. See more
While transporting Kirk back onto the Enterprise there is a close-up of the transporter operator's hands. His rank has changed and he is missing a finger on the right hand - clearly those are Scotty's hands and rank. See more
[regarding the development of an antidote
The urgency requires your personal attention in the laboratory.
My staff is working around the clock. My being there will not affect the biochemistry of any of the tests. This service requires my personal attention, Mr. Spock.