For a year, people learn to live with the spheres without suffering any specific changes. Even with the alien-looking spheres floating all over the sky, the CSAT is what matters the most to seniors of Sungjin High School. When the exam is just around the corner, one of the spheres drops on a military camp for the first time, and more shocking news awaits them.
Elenco: Shin Hyun-soo , Kim Ki-hae , Lim Se-mi , Ahn Do-gyu , Kim Su-gyeom , Woo Min-kyu , Yeo Joo-ha , Ahn Da-eun , Lee Yeon , Kim Min-chul , Kwon Eun-bin , Moon Sang-min , Choi Moon-hee , Sohee , Ro Jong-hyun , Ji Min-hyuk , Yoon Jong-bin , Shin Su-hyun , Hong Xa-bin , Shin Hye-ji , Lee Soon-won , Shin Myung-sung .