Just One Evil Act by Elizabeth George

Detective Sergeant Barbara Havers has very little in her life.  She has her job at Scotland Yard and she has a few friends.  One is Inspector Thomas Lynley and then there are her neighbors.  Taymullah Azhar is a research scientist, a Muslim working and living in London.  His ten year old daughter, Hadiyyah, is someone Barbara cherishes and she has become friends with the father as well.

Now Hadiyyah is gone.  Azhar had a relationship with an English woman named Angelina who is Hadiyyah's mother although the two never married.  Now Angelina has taken Hadiyyah and disappeared.  Azhar is desolate and begs Barbara to help him find his daughter.  Barbara is only too glad to help although it puts her tenuous job at Scotland Yard in more danger as she spends time on the search instead of putting her nose to the grindstone on her assignments.  With the help of a private detective, they discover Angelina has a new man and he has taken her and Hadiyyah to Italy.  Then the worst happens. 

Angelina shows up in London, shouting at Azhar to give her their daughter.  Since Azhar doesn't have her, it is plain that something has happened and someone else has Hadiyyah.  Although Barbara wants to go to Italy to help find the girl, her superior at the Yard absolutely refuses although Lynley is sent as the British representative to help the Italian police as he can.  Can the girl be found?

This is the eighteenth Inspector Lynley novel and is a bit of a departure as it focuses more on Detective Havers than on Lynley.  Havers's tendency to cut corners and do what she thinks is best instead of strictly following orders has her job on the line with a new Chief Inspector and this disruption couldn't have come at a worse time for her professionally.  She tries everything she can to find the little girl she has come to love even if it means sacrificing her own career and friendships.  This book is recommended to readers of mystery fiction.