The Secret Place (Dublin Murder Squad, #5)

A year ago, a boy was found murdered at a girls' boarding school, and the case remains unsolved. When sixteen-year-old Holly Mackey walks into Detective Stephen Moran's office with a photo and a caption, 'I KNOW WHO KILLED HIM', Moran and Detective Antoinette Conway reopen the case, navigating a web of friendships, rivalries, and relationships.