In Korea's feudal past, the deposed Crown Prince Lee Hun has been forced into a lonely exile by his cruel older brother, who has usurped the throne. Lee Hun fears for his life at every moment, as his brother plans to secure his place on the royal seat by killing him. Assassins and other schemes are a constant threat for Lee Hun, whose only true ally is his faithful and kind-hearted bodyguard Guem.

Meanwhile, in modern times, a high school student named Eun Ho loves paintings. In fact, art is his whole world. And when he is tasked with completing a mysterious painting, he is unexpectedly drawn back into the distant past, where he meets Lee Hun. The duo starts to form a close, romantic, and tender bond. But as the acting king grows restless, hoping to kill the exiled Crown Prince as soon as possible, Eun Ho begins to understand that he may be Lee Hun's best – or perhaps only – chance of survival...