Episode 4

In Part 1, Jeong Yeon gets attacked by a woman that claims that she's an alien and shows Woo Jin a picture of her with the toy star that he gave her 10 years ago. In Part 2, Bluebird leads Joon Hyeok to his past to find out who he is. It turns out he is Beom Gyun, and Bluebird is Jeong Yeon.