In an interview with tvN's "Flower of Evil" screenwriter Yoo Jung Hee, she talked about her drama and the title.
"Flower of Evil" is about Moon Chae Woon, a detective that suspects her husband Lee Joon Gi as a serial killer.
The series first gained attention with its surprising premise, which is -"What if you start to suspect the husband you've loved for 14 years might be a serial killer?" Yoo Jung Hee shared that she was thinking of various concepts and came up with an idea of having a husband who pretends to be a nobleman and a wife with an innocent heart.
Yoo Jung Hee also thought on the question that if someone will do their best for their partner to take their secret to the grave, that would maybe mean that they are living a lie. To make the story more exciting, she decided to team up the husband and wife as the detective and a serial killer.
Meanwhile, she also shared the story behind the title. While she was creating the character of Do Hyun Soo, she thought about Charles Baudelaire's Book 'Les Fleurs du mal' or 'The Flowers of Evil' in English translation. The poem of Charles Baudelaire is about chaos and anxiety that rises when the societal values became grand. She thought that it would be similar to the character of Do Hyun Soo, to make the viewers think of the beauty of a desperate life when they think of the drama.
'Flower of Evil' relays a message that even where the evil is buried, a flower can still bloom in there. The title of the drama represents Do Hyun Soo's image, which you can not define as black, white, or red and which also describes the character of Cha Ji Won, who learned to accept a new beginning after breaking down the walls inside her. (Via Soompi)