Oh Sehun and Huang Zitao have been friends since their childhood, but that soon changes when a war breaks out between South Korea and Zitao's homeland, China. The two have to separate and without knowing why, Sehun lives his life with some unanswered questions. Losing his best friend was all in the past and he tries to forget as he gets older. He wants to finish up his last year of college smoothly but when a new face enters one of his lecture classes, it seems impossible. The new face has the same facial features as Zitao. The only thing different about him is his sense in fashion and his personality. Sehun has a gut feeling it's Zitao, but he doesn't remember him being so coldhearted and emotionless. Little does Sehun know Zitao is working under cover as a Chinese spy. It isn't long before another war breaks out between South Korea and China. Zitao wants to keep his true identity hidden because Chinese spies, like himself, aren't welcome around here. But soon, bringing South Korea down to its knees no longer becomes Zitao's top priority. Sehun's affection towards him, and his safety does.