A Fateful Encounter.

Jang Cheon-woon was born the son of a third-rate martial artist. After losing his father and getting caught up with a gang, he struggles to survive a harsh life until one day he saves a dying old man by the river—Old Man Mu.

After beginning to live with the old man, Cheon-woon starts having strange dreams every night. In these dreams, he learns martial arts from the old man, and he gradually begins growing stronger in the real world as well.

One day, the Gucheonseong forces appear, having tracked down the old man. The old man, who had been hiding his identity, disappears, while Cheon-woon becomes entangled with them by chance and enters Gangryeonggok, Gucheonseong's martial arts training institution.

Through intense competition and relentless training, Cheon-woon grows stronger. Despite being mocked and looked down upon, he gradually proves his abilities and earns recognition. Eventually, he is selected as the bodyguard of the Young Lord.

But being a bodyguard isn't simply about protecting someone's life. It means surviving amid political schemes and deadly power struggles. Within Gucheonseong, factions seeking control of the sect begin to reveal themselves. The Young Lord senses the threats within, but the enemy's shadow has already reached deep inside.

As Cheon-woon protects the Young Lord while becoming a target himself, he makes a decision:

“I won't protect you by giving my life. I'll become invincible, never die, and protect you!”

With internal traitors and outside forces joining hands against them, the Young Lord's life is placed in grave danger. Cheon-woon must now become more than a mere bodyguard—he must become a martial artist capable of carving out his own destiny.

To survive the chaos engulfing him, he draws his sword.