Sol Kyung-gu
The crew built 26 different sets to create various spaces in the fictional 108-story Tower Sky such as a Chinese restaurant, elevators and a pedestrian overpass between the two blocks. For the scenes involving water on the 80th floor, actors Sol Kyung-gu and Kim Sang-kyung filmed in a water container set in Goyang City, Gyeonggi Province, without using stuntmen.