Dean Fredericks as Captain Frank Chapman

Coleen Gray as Liara

Anthony Dexter as Herron

Dolores Faith as Zetha

Francis X. Bushman as Sessom

Richard Weber as Lt. Ray Makonnen

Al Jarvis as Judge Eden

Dick Haynes as Col. Lansfield

Earl McDaniel as Capt. Leonard

Mike Marshall as Lt. White

John Herrin as Captain Beecher

Mel Curtis as Lt. Cutler

Jimmy Weldon as Lt. Webb

Akemi Tani as Communications Officer

Lori Lyons as Radar Officer

Richard Kiel as The Solarite

Susan Cembrowska as Juror

Marissa Mathes as Juror

Gloria Moreland as Juror

Judy Erickson as Juror

Sally Carter-Ihnat as Juror

Allyson Ames as Juror

Marion Thompson as Juror

Marvin Miller as Introductory Narrator (voice)

Warrene Ott as Ipsalata

Angelique Pettyjohn as Juror