In the mystical realm of Hoseon, protected by the tiger deity known as the Sable Tiger, Crown Prince Lee Hyo is born with formidable power but a cold, foreboding aura that forces the palace to hide his existence. Meanwhile, Seo Doram, a disgraced noble turned servant, is unexpectedly summoned to the palace with an astonishing decree: he is to become the Crown Princess. Confused and suspicious, Doram finds himself entangled in royal secrets, while the aloof prince oddly recalls a bond from their childhood... Just what could the Sable Tiger have in store for them both?