William is an unsuccessful guinea pig for a medical group interested in researching the common cold. He is soon fired and offered a job by the nearby National Atomic Research Center where they figure anyone who could fail at being a guinea pig is just what they need. They con William into thinking he will continue his guinea pig career by testing out some equipment for them before they send a group of astronauts to the moon.
| Actor | Role |
|---|---|
 Kenneth MoreWilliam Blood | William Blood |
 Shirley Anne FieldPolly | Polly |
 Norman BirdHerbert | Herbert |
 Michael HordernDr. Davidson | Dr. Davidson |
 John Glyn-JonesDr. Wilmot | Dr. Wilmot |
 Charles GrayLeo | Leo |
 Bernard HorsfallRex | Rex |
 Bruce BoaRoy | Roy |
 Noel PurcellProsecutor | Prosecutor |
 Ed DevereauxStorekeeper | Storekeeper |
 John PhillipsProfessor Stephens | Professor Stephens |
 Edward BurnhamTest Chamber Scientist | Test Chamber Scientist |
 Jeremy LloydJaguar Driver | Jaguar Driver |