In a mythical land called Arth, the inhabitants of the ancient city of Arthdal and its surrounding regions vie for power as they build a new society.

A dogged detective in pursuit of a faceless drug kingpin gets a much-needed break when a survivor from a mysterious factory explosion decides to help.

As a child, Park Hoon and his dad were kidnapped and taken to North Korea. He grew up there, learning to be a doctor just like his father. When Park Hoon escapes back to South Korea and begins work at a prestigious hospital, he makes it his goal to earn enough money to go back to North Korea to rescue his true love. He'll do anything to find her, but then he meets and falls for a mysterious woman who looks exactly like her.