According to the movie, the event that took place in this film is four years after train to Busan...while I find this movie enjoyable, I can't help but felt the wretched situation of the people (the survivors in quarantined S.Korea) to be too barbaric, uncivilized, cruel i.e exaggerated for a country that is highly industrialised to just turned into uncivilized brute (except few characters) just because of the zombie epidemic. All in all, it was a good one time watch!