Where the Heart Leads by Stephanie Laurens (2008, Hardcover)

Stephanie Laurens once again continues her "Cynster" series by revealing the gritty world of London streets and a young Scotland Yard.
Penelope Ashford is known as a high society rebel because she prefers to ignore her stations trappings and care for the forgotten orphans of London's streets. Recently, some of the children have gone missing mysteriously and so she hires private investigator Barnaby Adair, who has a keen sense of deduction and observation, to find out what has happened to them. Barnaby is intrigued by Penelope because of her determination and her beauty. They both enlist the help of Scotland Yard's Inspector Basil Stokes and the three of them end up infiltrating the notorious East End of the city. As they unravel the mystery of the missing boys they also uncover a dangerous lead that could threaten everything they hold dear in life.
If you love Johanna Lindsey's Mallory family then you will want to read this book also. Lots of suspense and steamy romance adding up to a super read!