The movie The Shape of Things to Come was necessarily a highly condensed version of Wells’ book, presented as a future history, which was a very long almost polemical treatise on the death of capitalism and the rise of socialism. Essentially, the Great Depression segues into World War Two without a break, and the heavy use of chemical weapons along with the outbreak of a pandemic- natural or bioweapon is never known- collapses what little is left of civilization. Only the Dictatorship of the Air survives to recreate society along rational, scientific lines.
Yes, Wells really takes that tone unironically. Holy Crap! H.G. Wells was a totalitarian!