In the episode "Arnold's Halloween," Cain is convinced that aliens would land in Hillwood on Halloween night. Mistaking them for Helga and the rest of the kids, he chases them down to the watertower outside the city.
However, after the watertower is damaged by explosives, water leaks out of the tank and washes off the makeup the kids were wearing. Douglas has to admit on television that the whole thing was a stunt, while Big Bob insults him and tells the audience to get some sleep.
This is Douglas Cain's only appearance in the show.
- Douglas Cain's voice is almost exactly like the voice of Brain, a character (who Maurice LaMarche also voiced) from the Warner Bros. show, Pinky and The Brain. This is because both characters are based on Orson Welles, who delivered the infamous War of the Worlds radio broadcast which is parodied in this episode. Maurice LaMarche has also impersonated Orson Welles on the animated sitcoms The Simpsons, The Critic, and Futurama, as well as the Tim Burton biopic Ed Wood.
- Douglas Cain's surname is possibly a reference to Citizen Kane, Orson Welles' best known movie.