After an asteroid draws an astronaut and his ship to its surface, he is miniaturized by the phantom planet's exotic atmosphere.
| Actor | Role |
|---|---|
 Dean FredericksCaptain Frank Chapman | Captain Frank Chapman |
 Coleen GrayLiara | Liara |
 Anthony DexterHerron | Herron |
 Dolores FaithZetha | Zetha |
 Francis X. BushmanSessom | Sessom |
| RRichard WeberLt. Ray Makonnen | Lt. Ray Makonnen |
| AAl JarvisJudge Eden | Judge Eden |
| DDick HaynesCol. Lansfield | Col. Lansfield |
| EEarl McDanielCapt. Leonard | Capt. Leonard |
 Mike MarshallLt. White | Lt. White |
| JJohn HerrinCaptain Beecher | Captain Beecher |
| MMel CurtisLt. Cutler | Lt. Cutler |
 Jimmy WeldonLt. Webb | Lt. Webb |
| AAkemi TaniCommunications Officer | Communications Officer |
| LLori LyonsRadar Officer | Radar Officer |
 Richard KielThe Solarite | The Solarite |
| SSusan CembrowskaJuror | Juror |
 Marissa MathesJuror | Juror |
| GGloria MorelandJuror | Juror |
| JJudy EricksonJuror | Juror |
| SSally Carter-IhnatJuror | Juror |
 Allyson AmesJuror | Juror |
| MMarion ThompsonJuror | Juror |
 Marvin MillerIntroductory Narrator (voice) | Introductory Narrator (voice) |
 Warrene OttIpsalata | Ipsalata |
 Angelique PettyjohnJuror | Juror |