In the Dark: A Novel (A DI Adam Fawley Novel, Book 2) by Cara Hunter
A woman and child are found in a senile professor's basement. A dead person is also found. DNA evidence shows the boy is the child of the man. The girl says they were slaves stuck down there. However, after detective work, it turns out that the man was the victim instead. This is a fairly gruesome mystery with many twists and turns.
A girl turns up missing and the detectives come in to investigate. The family attempts to be distraught, but seems reluctant to allow full access. The investigation covers lots of ground and ends up uncovering plenty of skeletons in the family's closet. This is a fast paced British thriller that ends up covering family issues, arson, child porn rings and a kidnapping and murder. We keep thinking we know what happened, only to have new twists and turns. The book also includes interludes of "social media" responses that help mirror much of the nonsense that happens in the real world. Even the wrapped up "conclusion" ends up being not as it seems.