100 Days My Prince — Characters & Cast

Initially emotional detachment and survival; evolves into defending Hong-shim and transforming Joseon into a just kingdom.

Begins as a cold, traumatized Crown Prince. After losing his memory, he transforms into 'Won-deuk', learning compassion, labor, and true love, before finally integrating Won-deuk's humanity with his royal authority to restore justice to Joseon.

Locating her separated older brother and securing safety and survival for herself and her adoptive father.

Witnessed her father's slaughter during the coup and grew into a resilient head of a village problem-solving agency. She softens her defensive exterior through her marriage to Won-deuk, eventually reclaiming her noble heritage without sacrificing personal autonomy.

Absolute political supremacy and dynastic entrenchment.

Orchestrated the original coup and relentlessly manipulates court officials, ordering Prince Yul's assassination to install his unborn grandchild on the throne, until his hubris leads to his battlefield downfall.

Meritocratic justice and protecting the people he cares for.

A brilliant official with prosopagnosia (face blindness) blocked by low birth status who can only recognize Hong-shim's face. Despite his unrequited feelings for her, he acts as an undercover double agent within Kim Cha-eon's faction to aid Crown Prince Yul.

Protecting his sister Yi-seo and securing freedom for himself and So-hye.

Yi-seo's long-lost older brother, coerced into serving as Kim Cha-eon's chief assassin to keep his sister alive. He enters a forbidden romance with Crown Princess Kim So-hye, ultimately sacrificing his life in an attempt to escape the cycle of violence.