Gong Yoo

Gong Yoo went on a diet for three months to reduce his body fat. He learned the Russian martial art Systema for the film's fight scenes, and performed car chases, rock climbing and skydiving at the Han River without using stuntmen, for his role on The Suspect back in 2013.

[On his experience on Train to Busan] I thought zombie and action films were a piece of cake, but I struggled.