bad plot twist

we thought it would be a suspenseful serie, very detective like... but all mysteries goes away in one episode, with a bad plot twist, trying to surprise us with the killer identity... it's not even how a woman killer would do but whatever. Realism shouldn't be expected in kdrama. The main character is complicating everything with her unnecessary bad choices. The characters discover her secret in goofy ways, and they NEVER communicate, which is very frustrating. It had a great concept... i liked the humor very much and enjoyed only the first episodes.