Kang Seulgi is a famous mystery novelist. Bored and suffering from writer's block, she kills off the main character in her successful book series. She is brought in by the Seoul Metropolitan Police Department for questioning regarding a copy-cat murder based on one of her novels. She is intrigued by Bae Joohyun, the detective assigned to the case. Seulgi decides to use Joohyun as her muse for Bae Irene, the main character of her next book series and uses her friendship with the mayor