Things to Come opens with a near-future forecast of Christmas 1940 in the metropolis of Everytown (obviously London), a city threatened by world war. Pacifist intellectuals, such as John Cabal (Massey), try to turn the tide. But Cabal's efforts go unheeded by the self-interested classes, and war arrives with tanks and aeroplanes and gas bombs. Everytown is destroyed by air raids (dramatically enacted four years before the real thing).The war continues for thirty years, its original purpose forgotten. As a result, civilization degenerates while "the Wandering Sickness" and devastation accelerate the spiral down until 1970, when the world has crumbled into a balkanized "Mad Max" Dark Ages. Everytown is ruled by a barbaric warlord, the Boss (Ralph Richardson), as the war continues on a Medieval scale.
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Things to come on IMDB