Kang Do-Hyun, a childhood friend of Crown Prince Lee Chang, is a soldier for the army, but personally chosen by his friend to be by his side.

One night, they find out Chang's father's death was being covered up by the Queen Consort, Do-Hyun, Chang, and Mu-Yeong try whatever they can to expose the true intentions, but it wasn't long before a plague outbreak starts to spread across their land.

The three fight to save lives from infected monsters while looking to expose the Queen and her scandalous actions, but while investigating the case of the outbreak, Chang, Mu-Yeong, and Do-Hyun meet Seo-Bi, a physician who survived the plague in her village.

They all work together, and become very good friends as they fight the plague and help each other out, but somehow, Do-Hyun starts to feel attracted to Seo-Bi, during the search for the resurrection plant. How does she feel about him?