Seasons & Episode
In part 1, After Woo Jin shows Jeong Yeon the photo of them together ten years ago, she gets confused about who she is. In part 2, Beom Gyun meets Jeong Yeon who had become Bluebird. Meanwhile, Ho Soo starts having nosebleed as he slowly recovers his memories.
In part 1, Woo Jin finds Beom Gyun in the house they used to live in when they were little. In part 2, the chairman of Human B asks to meet Beom Gyun. But it is discovered that the chairman is Minister Park Dong Geon. Beom Gyun asks where Woo Jin is.
In Part 1, Dong Geon and Human B join hands and try to come up with a plan to get Woo Jin and Jeong Yeon. In Part 2, Jeong Yeon and Joon Hyeok go to Human B to find Woo Jin after finding out that their supercomputer won’t work without Woo Jin. However, the supercomputer crashes.
The person coming down the stairs turned out to be Woo Jin’s clone. At first, Joon Hyeok denies that he’s Woo Jin because of the real Woo Jin who died. But as the clone tells him his memory of the day he disappeared, he apologizes. He says he’s sorry for letting him go there alone.
Joon Hyeok suspects that Mayor Yoon has seen something that can be used against Dong Geon. Since Jeong Yeon can unlock his memories, they decide to take him out of Human B’s hands and unlock it. And since Min Young is a doctor, she sneaks in to the hospital to take him out.
After Aliens arrive, the story takes place in two time streams: 2017 and 2037. In twenty years, and by 2037, the world has been divided into a “Smart Earth” where artificial intelligence has created a utopian environment in which no diseases or crimes exist, and an “Ordinary Earth” where people still suffer from rampant plague and lawlessness.