The Mitford Murders by Jessica Fellowes

From one of the Downton Abbey creators comes a delicious mystery sure to keep Miss Mary up at night. Louisa luckily flees her abusive uncle by jumping off a train and then ends up as a nursery maid for the Mitfords. She is happy at the manor house and becomes very fond of the oldest daughter Nancy. Soon the two, with the aid of a young train investigator, become engrossed in solving a horrible murder- that of a nurse who was killed on a train and discovered as Louisa ended up at the station. The problem is that this murder investigation comes dangerously close to uncovering Louisa's secret past. Louisa must decide who she can confide in and somehow keep the young and impetuous Nancy Mitford out of trouble. Adventure, discreet romance and an Agatha Christie worthy mystery - who murdered Nurse Flo is sure to be gossiped about upstairs and downstairs.