At first glance this is a police procedural but it is really a cozy mystery, or it could be a mixture of the two. To be honest it doesn't matter if it isn't categorised as this book defies Categorisation. Inspector Witherspoon of Scotland Yard is investigating the death of a seemingly upright Doctor. The Inspector does' know it but it is really his housekeeper, Mrs Jeffries who is the solving the murder. She is helped by a diverse crew, compromising the remainder of the household servants. This will give you an idea of how different this book is. The characterisation is spot on with Mrs Jeffries being a particular shining star. The Inspector, although somewhat puzzled by the whole thing, is endearing and I found myself wanting to look after him. There are several even more eccentric characters and those all take their place, no matter how minor their roles.
The book is just one of a whole slew of Victorian Murder Mysteries all starring Mrs Jeffries. I am sure that you are already realising that Mrs Jeffries is the real star of the books. This is the first one I have read and I cannot wait to read another. I haven't a clue where this fits into the series but it really doesn't matter. Back story is integrated well to support the plot. Another one I would highly recommend.