The Longest Shoot

Experiment: a movie which chronicles the lives of a group of people from youth to old age, without using makeup or different actors. That is, it's some 20 years in the making. Huge amounts of footage are shot, and then cut down to feature length in the end.
You'd expect the plot to be affected by world history during those years. But such decade-spanning drama already exists in the form of soaps; and strangely, exactly those series present a cocoon-like, time-independent world view, in which only names and faces ever change.
So the idea's still good. Now to execute it.