George T. Simms (Bailey), Frank Graham (Manfish), Ron Stein (Forrester), Ray Didsbury (Collins) Lou Elias (Crewman)
As Borgman prepares to irradiate his first fish at the beginning of the show, he orders Hansjurg to first remove the tubing. Not only is the tubing left in the tank, but in the instant before the radiation flashes, it looks as if it's still attached to the fish.
Crane is ordered to get into his wetsuit, and he angrily undoes the buttons of his shirt. The camera followed Borgman across the room. As Crane looks at the tanks of liquid oxygen, his shirt is buttoned back up.
Borgman speaks to Hansjurg about his enemy, Admiral Park)
Borgman: When a man nearly destroys you, you either hate him, or you fear him -- just as you fear me.
Victor Lundin attempted to put some depth into the scene where he strangled Borgman, having a lengthy close-up showing his anguish at killing the man he both respected and feared. When Allen saw the rushes, he snapped at the director that they were not doing Playhouse 90, and trimmed it down to two seconds.
Richard Basehart did not appear in this episode due to illness. According to the book Science Fiction Television Series, by Mark Phillips and Frank Garcia, Gary Merrill was slated to become a permanent replacement for Basehart if it became medically necessary.