Matthew Gore is an intelligent boy chosen by a mysterious extraterrestrial visitor to be a source of information about life on Earth. As his schoolwork and artistic talent improve dramatically he arouses the suspicion of powerful groups who wish to tap into the amazing fund of knowledge to which he is now party.
| Actor | Role |
|---|---|
 Carol DrinkwaterMary Gore | Mary Gore |
 James HazeldineDavid Gore | David Gore |
 Andrew EllamsMatthew Gore | Matthew Gore |
| ZZoë HartPolly Gore | Polly Gore |
 Devin StanfieldColin | Colin |
 Glynis BrooksChocky | Chocky |
 James GreeneMr. Trimble | Mr. Trimble |
| PPenny BrownjohnPhyl | Phyl |
 Colin McCormackAlan | Alan |
| KKelita GroomJane | Jane |
| JJonathan JacksonMark | Mark |
| PP.J. BickfordRoger | Roger |
| CCatherine ElcombeSusan | Susan |
 Jeremy BullochLandis | Landis |
 John GrilloSir William Thorbe | Sir William Thorbe |
| JJohn PenningtonInspector Maggs | Inspector Maggs |
| LLynne PearsonMiss Blayde | Miss Blayde |
| DDerek BroomePolice Constable | Police Constable |
| MMartyn LewisNewsreader | Newsreader |
| PPatrick BlackwellBoatman | Boatman |
| KKathleen CottyEmma | Emma |
| LLeo DolanPostman | Postman |
| GGary RaynsfordPoliceman | Policeman |
 Deborah FairfaxGirl Reporter | Girl Reporter |
 Janet HenfreyCranky Woman | Cranky Woman |
| BBrian RedheadInterviewer | Interviewer |
 Gary WatsonRadio Reporter | Radio Reporter |