The cardinal sin this movie commits is having characters frozen in fear by the zombies, standing still in shock instead of doing literally anything else, and it does this in most scenes. If you can get past that, though, everything else about this movie is great. Zombies on a train presents a myriad of interesting situations, and this movie goes through them one by one. It’s everything we’ve come to expect from a zombie movie done very well in an interesting location.
Closest Comparison: It’s 28 Days Later by way of Snowpiercer
Setting: Zombie Apocalypse
Plot: Feel-good Family Drama
Tone: Action