When a robot dog from the future pops up in their backyard on a mission to help them, 11-year-old James and his beloved golden retriever, Rex, learn that it is up to them to save the world from Dr. Apocalypse, an evil scientist, and his wily robotic Destructo-Cat.
| Actor | Role |
|---|---|
 Ben BrowderRobert Miller | Robert Miller |
 Kalvin StingerJames Miller | James Miller |
 Ethan PhillipsRandy Jenkins / Professor Apocalypse | Randy Jenkins / Professor Apocalypse |
 Maggie ScottKara Reese | Kara Reese |
 Rocky MyersAdult James | Adult James |
| CChristopher BusterKyle | Kyle |
| GGunnar J. RussellPosse | Posse |
| CColeson HolmanPosse | Posse |
| SSiaki SiiPosse | Posse |
 Blake WebbOfficer Jones | Officer Jones |
| CClinton ColtrinAgent Sheffield | Agent Sheffield |
| CCasey ScottNews Anchor | News Anchor |
| KKendra HitchcockEMT | EMT |
 Adam JohnsonRoboRex (voice) | RoboRex (voice) |
| AAmannda AshbyMisses Nelson | Misses Nelson |