Falls the Shadow by William Lashner
Falls the Shadow
A beautiful young woman is dead, her husband convicted of the grisly murder. In seeking his acquittal, defense attorney Victor Carl must confront not only a determined prosecutor and a police detective who might have set up his client but also a strange dentist named Bob.
Thanks to Bob, Victor is suddenly dressing better and dating a stunning woman, and both his economic prospects and his teeth are gleaming. Everything is good, until Victor finds a troubling connection between Bob and the murdered wife. Is Bob a kind of saint, or is this obsessive Good Samaritan, in reality, a murderer?