In the fifth book in the series, Irene is called in the middle of the night to go to Paris and investigate a murder. A couple of prostitutes were killed in a gruesome manner and some pretty important people are liable to have their reputation tarnished. CND delicately avoids the gore and leaves a lot of the details to the reader's imagination. Everyone thinks Jack the Ripper is responsible, but who is he? Sherlock Holmes and Dr. Watson investigate. Irene meets a young woman at the brothel and takes her in, her nickname is Pink, because of the way she blushes. Nell is kidnapped, Godfrey is missing, and Irene actually loses her poise. Pink makes an interesting substitute for Nell in the narration, and this turns out to be a two part story, continued in Castle Rouge