Land of the Giants

50-year technology gap: a metal detector capable of sensing a given metal within a distance of miles.

Within walking distance: Kobick's SID office (although he may have taken over the previously-seen police station) and a food warehouse

Why does Kobick keep turning off the detector? Several times it would make more sense for him to keep it on and look for other sources of inella metal, such as when he is tracking Mark, Fitzhugh, and Valerie and finds the broach.

So, did any of the other Earth expeditions have inella metal on them? If so, the teenagers from "The Lost Ones" may be in big trouble.

Although this is Inspector Kobick's first aired appearance, the Earthlings already seem to know his name. In production order this is the second episode featuring Kobick: "Genius at Work" precedes it.