I went to see the new movie Snowpiercer on the advice of a younger colleague, and I’m very glad I did. It’s a highly political science-fiction film that succeeds in spite of its politics. The plot has to do with a post-apocalyptic train on which Earth’s last survivors circle the world on an endless loop — and on which the oppressed peasants at the back of the train finally decide to revolt against the oppressors up at the front.

Yes, it’s a pretty heavy-handed Marxist allegory. Which makes it all the more remarkable that the film succeeds aesthetically and as pure entertainment. And it does: It’s a triumph of the imagination, as the train and its residents coalesce into a fully realized and emotionally captivating setting and narrative. There are some great performances, notably by Tilda Swinton as a helmet-haired, clipped-British-accented villain who is herself middle-class but is a craven servant of the upper classes. (It would of course be completely absurd to suggest that she is meant to be a caricature of any particular U.K. prime minister of the past three decades or so. Sorry, sarcasm off now.) And, most important of all, a deep truth about the human condition emerges past all the politicizing: Man’s fundamental goal, his essence, is to transcend his circumstances. This is where the film’s allegory works best, and most successfully overcomes its Marxist roots: in stressing that the most important issue is not, as the materialist Marxist analysis would insist, who controls the train — but rather, the importance of realizing that the train is not the fundamental reality.

This is an exciting and beautifully filmed adventure story; the train is an excellent set, a realized world that manages, amazingly, to avoid claustrophobia. There is violence, but not that much more than occurs in the typical Hollywood big-budget actioner. The film is now available on a number of online video-streaming services, but try to see it in its big-screen limited release if you can; it’s a visual marvel.