La terra dei giganti

If there was a happy-ending episode to conclude the series, it may have been like this: The seven people on the Spindrift didn't travel through time or distant space but were shrunk like the movie "Fantastic Voyage" and landed on Earth in an English speaking place at the present time. That's a similar concept as the movie "Planet of the Apes". That's why we see the same cultures, fashions and technology as Earth of the late '60s. Some familiar products and objects appear but are just twelve times in larger scale except the audio level. The Captain insists he saw Earth in "On a Clear Night You Can See Earth" but it was his wishful thinking or mental distortion.