Uncredited cast listings:
Robert Payne (Helsman), Patrick Culliton (Winchman), Nigel Evan McKeand (Sonar), and Paul Kremin (Aleksei's voice)
Given that the Flying Sub was not seen until the second episode, first-time viewers must have been puzzled at the shot of it in the closing credits.
In this episode, we learn that the diving bell has a name: Apple One.
In this episode (and the forthcoming whale episode "The Shape of Doom") the tranquilizer used on the whale is called "Anodyne". "Anodyne" is simply an old-fashioned pharmaceutical term meaning "painkiller". Aspirin is an anodyne. So is Novocaine or Ben-Gay.
In spite of the fact that the opening credits show the Seaview with her new Flying Sub hatch on the bottom, stock footage shows the underside of the sub with just the Season One running lights.
As in many episodes following, the Seaview alternates between having 4 and 8 nose windows. This was due to the use of first season stock footage.
(Katya has just realized that they have been swallowed.)
Katya: Impossible. There is no whale now in existance big enough to swallow this.
Nelson: The archeoceti.
Katya: Long ago extinct.
Nelson: Well, to revive a tired old joke, you know it and I know it, but perhaps he doesn't.
Katya: That young man. . .what dialect does he speak?
Kowalski: Him, ma'am? That's Riley. (pause) He's a surfer.
Katya: 'Surf' is one of the United States?
Kowalski: Yes, ma'am. It's the state of being, like, way out.
Riley: Man, dig that fish!
According to the book Science Fiction Television Series, James Doohan was originally offered the role of Sharkey, but turned it down in favor of the role of Scotty on Star Trek. (Filming of the second Star Trek pilot "Where No Man Has Gone Before" began in the summer of 1965.) Walter Koenig (later to become Ensign Chekov of Star Trek) was one of the actors who tested for the role of Stu Riley.
The music by the great Jerry Goldsmith is exciting and unique. The episode even sported a provocative new title theme, composed by Goldsmith and used in this episode only. However, several composers of the next few episodes used the theme as the basis for their scores. Obviously, the new theme was meant to last the season (at least), however Irwin Allen decided to use the original Sawtell theme for the remainder of the series. The reason for this is unknown, although the original Sawtell theme is a fan favorite. While I feel that Goldsmith's theme is appropriate for the direction the show was to go in, I cannot deny the beauty and "nautical" feel of Sawtell's classic music. This would not be the last time Goldsmith's work is replaced by producers of film and television. The score (in an abbreviated form) is available from GNP Crescendo.
This is the first episode broadcast in color. While the sub was redesigned (the eight windows becoming four, the observation nose now attached to the control room, etc.) much of the model footage was from the first season. In fact, all of the technology in this episode reflects the first season. There is no sign of the Flying Sub at all.
The majority of the whale footage was taken from the season one episode "Ghost Of Moby Dick" and color-tinted.