An "unknown force" declares war against planet Earth when the United Nations disobeys warnings to cease and desist in its attempts at assembling the first satellite in the atmosphere.
| Actor | Role |
|---|---|
 Dick MillerDave Boyer | Dave Boyer |
 Susan CabotSybil Carrington | Sybil Carrington |
 Richard DevonDr. Pol Van Ponder | Dr. Pol Van Ponder |
 Robert ShayneCole Hotchkiss | Cole Hotchkiss |
 Michael FoxJason ibn Akad | Jason ibn Akad |
 Eric SinclairDr. Howard Lazar | Dr. Howard Lazar |
 Jered BarclayJohn Compo | John Compo |
 John BrinkleyBrunet Helmsman of Satellite | Brunet Helmsman of Satellite |
| TTony MillerBlond Helmsman of Satellite | Blond Helmsman of Satellite |
 Bruno VeSotaMr. LeMoine | Mr. LeMoine |
| JJay SayerJay | Jay |
 Mitzi McCallMitzi | Mitzi |
 Roy GordonThe President | The President |
 Beach DickersonCrewman with Gun | Crewman with Gun |
| JJim KnightReporter | Reporter |
 Roger CormanGround Control (uncredited) | Ground Control (uncredited) |
| JJames GonzalezTechnician (uncredited) | Technician (uncredited) |
| PPat ClementReporter (uncredited) | Reporter (uncredited) |
| NNorman StevansReporter (uncredited) | Reporter (uncredited) |