The lost thing is a short CG animation created by Australian artist and narrated by a famous comedian.
The story was settled in a mysterious world which isn't like our world. And there are so many things that are lost by someone. One day a boy finds a lost thing and tries to look for the person or place where the lost thing belongs to.
In the end, a boy finds a place here many lost things live.
In this film, I guess it is trying to tell us that we tend to look too much on our matters and it is is important to look back our old days sometimes.