THE BIRTHDAY PRESENT by Barbara Vine, 2008.

I finished this last night, a rather odd book that intrigued me enough that I kept reading. The story involves an unmarried British MP named Ivor and his marrried mistress, Hebe, who enjoy sex games. For her birthday, he arranges for her to be kidnapped, bound and gagged and delivered to his home. However, there is a terrible accident, and Hebe and one of the kidnappers are killed, and Ivor fears a political scandal that will break over his head. Over time, there are threatening letters, hints, and incidents that play into his fear, and involve other characters and their agendas. A good psychological tale, with interesting characters and motivations, dark desires, and obsessive behavior. This is a slowly unfolding story that reveals bits that eventually come together to form the whole complex picture. If you're into this type of suspense, this is worth the time. Barbara Vine is aka Ruth Rendell.