All hail the train!
There's nothing new or interesting about dystopian, apocalyptic futures, be they Snowball Earths or otherwise. Suppressed lower classes rioting against a perverted bourgeoisie that devours what few resources left - dime a dozen. The fascinating, if heightened-suspension-of-disbelief-demanding thing Snowpiercer does to make it fresh is monumentally decreasing the scale of the event. What happens when a civil uprising takes place on a single train holding all of humanity, brought back to perhaps a few hundred?
The setting for this post-catastrophic society is strictly linear: the lower class rots at the back of the train and every wagon they conquer is a step up the food chain. No shortcuts allowed: the outside is a blistering wasteland that'll freeze you in seven minutes. The only way to pass from one side to the other is by traveling through the entire known world in so many railway cars. From ultimate squalor to places that suddenly have windows, air conditioning, real food, luxury... Since we view the story exclusively from the eyes of Curtis, part of the train's human detritus, we feast our hungry eyes upon it along with him and his fellow revolutionaries. Drip-feeding new wagons to us is the film's delight and prerogative. As they go from shocking to comforting to freaking bonkers, the scrappy rebel heroes are made privy to the many secrets of this train and their misbegotten status.
Don't expect any of these secrets to make a lot of sense. As ever, the excuses of the upper class are poorly developed and their motives flimsier than cardboard. Doesn't matter. Snowpiercer takes such pleasure in inventing funny, wicked, tense or scary scenes and surprises, you quickly learn to love it no matter what it does. Inventive is the word for the whole experience. Fight scenes shot through night vision goggles, body mutilations while a delightful Tilda Swinton stumbles through a speech, a stand-off against an army of fetish clubbers and even a touch of violent gun play set in kindergarten. Don't be surprised to see the influence of Old Boy here and there: this film's ultimately a Korean venture. All the better for it. The star of the show may be Chris Evans as Curtis, right along his side are Song Kang-ho and Go Ah-sung as an imprisoned technician slash drug addict and her daughter.
Equally reminiscent of Old Boy is Curtis' reveal at the end of the terrible things that befell him in the past. Snowpiercer loses some of its momentum at this juncture, winding down during a long confrontation with the train's master. It's here that Curtis ultimately loses the title of lead and transfers it to the Koreans. He suddenly forgets what he came here for, and what was the purpose of this whole venture again? His arc fizzles out. The ending doesn't fulfill at all, trading the story's flashes of brilliant, if unbelievable world building for a big, dull explosion that wipes all the stakes away. Symbolically sound, narratively not so much.
But let's not let a little thing like an ending spoil the many things on offer here. By scaling back both humanity and its habitat to a single, linear strand, Snowpiercer brings fantastic close quarters conflict and forces itself to work with that. Limitation is often the mother of great invention.