After a Qing-mandated exile, Grand Prince Jinhan returns to a hostile palace. He later encounters an intriguing baduk player who proves to be elusive.

After facing Yi In in a game of baduk, Kang Hee-soo develops feelings for him. Meanwhile, Yi Seon grows increasingly ill, creating a succession crisis.

Kim Myung-ha urges Hee-soo to stop her ruse. When a royal crisis arises, Kang Hang-soon performs a selfless act — but Kim Jong-bae schemes against Yi In.

After a confrontation with Yi Seon, Yi In ascends to the throne — but not without opposition. In the process, he cruelly turns a blind eye to Hee-soo.

Yi In summons Myung-ha to the palace and appoints him to a special role. To get the attention of the king, Hee-soo takes part in the baduk examination.

Hee-soo receives a stern warning from Yi In upon becoming his official baduk companion, later becoming entangled in a political ploy by the queen dowager.

Yi In begins to suspect a suspicious relationship between Myung-ha and Hee-soo. Later, Hee-soo joins the Grand Prince on a royal trip with the King.

After rumors of Yi In's affection toward Hee-soo spread like wildfire, the palace arranges a royal night of intimacy for him — despite true feelings.

After a night of intimacy, Yi In and Hee-soo navigate their complicated feelings. In an attempt to oust Hee-soo, Park Jong-hwan wages a bet with Yi In.

The Qing makes a contentious demand, and Yi In's decision in the matter forces Hee-soo to carry out her own plan — but last-minute complications arise.

As Jong-hwan gets close to catching the faux-princess, Hee-soo puts her faith in Yi In — struggling with her growing feelings for him.

After lightning ignites a fire, Yi In sees it as a sign from above. As Queen Oh's health falters, Hee-soo strives to protect the Grand Prince's fate.

A last-minute change of heart gravely injures Hee-soo — prompting questions around her gender. Later, Yi In reveals the fate of her father to her.

In a vulnerable moment, Yi In shares the secret of his ascension with Hee-soo. Jong-hwan plans a counterattack for Yi In's investigation of past events.

After Senior Court Lady Dong's tragedy, Yi In aims to punish the one responsible. Queen Dowager Park finally learns the truth about Hee-soo's gender.

Despite Yi In’s opposition, Hee-soo embarks on a dangerous journey to visit her father. But as months pass, their reunion remains uncertain.