28 Days Later influenced Train to Busan

The sprinting infected is 28 Days Later's invention and Train to Busan runs on it entirely: a crowd that converts in seconds, so distance stops being safety and every carriage door becomes the plot. Yeon Sang-ho's additions are his own, a commuter train as the confined space and a fund manager who has to stop optimising, but the creature and its speed come from Boyle.