Forbidden Legacy

When a remote farmhouse burglary results in the death of one of the two elderly sisters living there the police are led to believe only a few trinkets were stolen. But then the surviving sister seeks out Theo Stern and admits that during the raid a priceless painting was also taken. But why were the police kept in the dark? She confides all to Stern, swearing him to secrecy and begging for his help to retrieve the painting.
Stern's encounters danger at every turn when his investigations lead him from a wealthy, influential French banker with links to the French underworld to a vicious London abduction and a twenty year reign of unsolved crimes in the UK?