Being picky...

Rating: 2/10 (3 August 2018)

The writers had a reasonable idea, but unfortunately have no idea how an actual 21st century modern railway works!
Things that I didn't know;
Trains are like buses and can be routed on a whim without the need for Signalling or Signalers/dispatchers to control movements.
Under a zombie attack railways will still function at 100%, including signalling, the electrical supply to the trains, signals and turnouts.
Mobile phone networks will still work and not get overwhelmed, and handset batteries last for hours without charge
On the modern railway, the car lights go out in tunnels to give protagonists a chance
Zombies can be stopped by unlockable sliding doors between cars.
Some elder Korean women only look about 35 years old women with wigs on
When a track is blocked, you can just take any from any yard or track and go where you want regardless of what the signalling dictates.
You can easily run and jump onto a runaway loco that's traveling in excess of 20MPH whilst carrying a child and if you're pregnant
Never trust the middle aged business executive, he'll just sacrifice everyone else to survive simply to get infected later