Shows such as this were never meant to be taken seriously. They were totally tongue-in-cheek and were not meant to be deep shows with some universal message.
The show was about a US spaceship-the Spindrift-which went through some kind of space warp and ended up in a world identical to Earth-the only difference being that everything was much much bigger. The crew was led by Captain Steve Burton and they tried in vain to fix their ship and evade giant people and giant animals.
It was a great show. Like other Irwin Allen shows, the heroes were always out of their depth. Minature people against giants-fantastic idea. Don't expect anything deep when watching this-just a damn fine show.