Three men gamble their lives in space to change the history of the world
| Actor | Role |
|---|---|
 William LundiganDr. Richard Donald Stanton | Dr. Richard Donald Stanton |
 Herbert MarshallDr. Donald L. Stanton / Narrator | Dr. Donald L. Stanton / Narrator |
 Richard CarlsonDr. Jerry Lockwood | Dr. Jerry Lockwood |
 Martha HyerDr. Jane Flynn | Dr. Jane Flynn |
 Dawn AddamsSusan Manners | Susan Manners |
 Robert KarnesWalter Gordon | Walter Gordon |
 Lawrence DobkinDr. Delmar | Dr. Delmar |
 George EldredgeDr. Paul Dryden | Dr. Paul Dryden |
 Dan RissDr. Frank Werner | Dr. Frank Werner |
 Michael FoxDr. Klinger | Dr. Klinger |
 King DonovanJames O'Herli | James O'Herli |
| KKem DibbsDavid Wells | David Wells |
 James BestDr. Sidney K. Fuller | Dr. Sidney K. Fuller |