Season 1

So Jin fails to meet Yeon Woo at the Han River, and she runs into Kang Hoon instead. Just when she thought she failed the experiment, she realizes that her telepathic message could've been interfered. So Jin and Yeon Woo go on a trip to Gapyeong to see a celestial show. Kang Hoon joins them in secret to stop Yeon Woo from hitting on So Jin.

Yeon-woo saves So-jin from Oh Sang-min, her ex. Yeon-woo tries to kiss So-jin, and Kang-hoon witnesses it. Kang-hoon warns Yeon-woo to stay away from So-jin and not to hurt her. However, Yeon-woo decides to continue with the experiment So-jin suggested. Meanwhile, seeing how Yeon-woo keeps appearing in her path, So-jin starts to believe that the two of them share a telepathic gene.

So-jin finds out that Yeon-woo has the Indecent Octopus Tentacles Gene and thinks he's a cheater. She breaks the news to Yeon-woo, which leaves him flabbergasted. Meanwhile, the woman Yeon-woo's father is seeing gets the DNA test done for the baby in her womb and hears shocking news.

So-jin discovers that Yeon-woo has a special scent that she's attracted to, so she decides to figure out if he's her DNA lover. So-jin meets her sister and mother to commemorate her dad's death anniversary at Kang-hoon's restaurant. The family gathering doesn't go too well, and they end up fighting. Yeon-woo, who happens to be at the restaurant, overhears So-jin's family's history.

Yeon-woo is still in trauma from what So-jin did to him in his house the other night. He demands that So-jin make an antidote to the hair growth solution within 24 hours. Meanwhile, while looking into the DNA of one of Yeon-woo's patients, So-jin makes an important discovery. She hurries to Yeon-woo's hospital to save a life.

So-jin, a DNA researcher, gets dumped by his boyfriend, Sang-min. Heartbroken, she drinks too much and breaks into a stranger's house. Yeon-woo, a successful gynaecologist, breaks up with his girlfriend as he gets sick of her. Kang-hoon, a hardworking firefighter, finds a pregnant woman unconscious. Meanwhile, So-jin witnesses Sang-min walking down the street with a woman she knows.