When 'Snowpiercer' was first announced, it immediately drew attention because it had attached such a diverse and international cast. Bong Joon-Ho had managed to assemble several A-list global stars for his post-apocalyptic train movie, and from early reviews, it certainly doesn't look like he's let anyone down.
The review from Variety was glowing, with the reviewer saying, "[A]n enormously ambitious, visually stunning and richly satisfying futuristic epic from the gifted Korean genre director Bong Joon-ho. A rare high-end sci-fi/fantasy pic made completely outside the studio system, and that even rarer case of an acclaimed foreign helmer working in English with no appreciable loss of his distinctive visual and storytelling style."
Twitch also had an extremely strong review, saying, "Though it was never going to be a sunny ride, the sheer desperation, violence and madness on display throughout Snowpiercer’s 125 minutes make it one of the most dystopian films we’ve seen in quite some time." Some of the reviews state that it might be too dark and too violent to appeal to a larger audience, but I don't think that will be as much of an issue as they think. Audiences nowadays are very used to violence in their movies, and dystopian films are at their peak in pop culture.
'Snowpiercer' stars Chris Evans, Tilda Swinton, Octavia Spencer, Alison Pill, Jamie Bell, Ed Harris, John Hurt, Ewen Bremner, and Kang-ho Song.