I saw this episode of Out of this World while babysitting for a neighbour when I was just turned 13 myself. It made a huge impression on me and has haunted me ever since.
I was reminded of it when watching James Cameron's impressive 3D film, Avatar.
What was so impressive and haunting for me was that it portrayed humans rather than aliens as the baddies, and the fact that you only realise this at the very end, with the last words that are spoken.
We know that there are bad human beings, but assume that we ourselves and those who teach and lead us are basically good. Only, we are not nearly as good as we like to believe, and collectively (just look at the state of the world) it is evil which predominates. We continue to plunder and spoil our planet, and to exploit our fellow human beings, but rationalise our behaviour as being the best that can be expected of us, and that it is OTHERS' bad attitudes and behaviours, rather than our own, which are responsible for things not being better than they are.