Good Girl, Bad Girl is the first in Michael Robotham's Cyrus Haven series. Cyrus Haven was in kinship care with his grandparents from the age of 13, after his family was killed by Cyrus' older brother. At the opening to Good Girl, Bad Girl, Haven is introduced to Evie Cormac who’s living in Langford Hall, “a secure children’s home” or youth detention centre in Nottingham. The resident social worker, a friend of Haven’s from university called Guthry, thinks Haven might be able to help Evie, since they have in common a loss of family.

Evie has lots of other traumas too. Like having lived in a house with a dead body for months, and then going into the foster care system. Cyrus thinks he can help Evie, although he recognises she has considerable unpacked traumed. Cyrus also discovers that Evie has an uncanny ability to detect the lies that people tell.