 Key themes that provide an important backdrop for the film are the Great Depression, a sense of political and social unrest with the related issue of the powerful vs. the weak, and a sense that the country is entering an age of science that will bring great wonders to all. Lang (Macy), a drill press operator in a huge, ominous factory, cares for his blind sister (LuPone) and the two of them dream of a way to a better life with his water engine. The film is about hopes and dreams against the reality of the Depression and powerful forces.