Tom Tomorrow’s written a lyrical hymn to The Land of the Giants on his blog, with many lovely illustrations:
So essentially, you had three cardboard cutout male heroes, two damsels in distress, a conniving con artist and a little boy who either refused to see the truth about the con artist, or understood the deeper goodness which lay buried within him. And little Chipper, who was constantly running off, causing young Barry to follow, and inevitably get captured, and eventually rescued. And there you have the basic story arc of any given episode in a nutshell: someone would get captured by a giant–probably a scientist intent on dissection, because of course when you discover a living ten-inch-tall human being, your first natural impulse is to tape them down and have at them with a scalpel–and then rescued by the other castaways, a process which invariably involved the aforementioned giant safety pin, which could be tossed up onto a table where it would stick securely, allowing the little people to climb up and free their comrades (alternately, a nearby electrical cord leading up to the table could be used in a pinch) who, once free, would scamper back down to the ground and escape through a handy heating duct. (The characters also spent a lot of time hiding in giant cameras and dialing giant telephones with giant pencils, and generally thrashing around pretending to be unable to escape from giant, strangely immobile hands.)
(Thanks, Zed!)