A child abduction with elements of the Elizabeth Smart case triggers this pallid romantic suspense novel from Edgar-finalist MacDonald (The Unforgiven
). When she was nine, Tess DeGraff witnessed the knifepoint kidnapping of her teenage sister, Phoebe, by a wild-eyed man with a ponytail who warned her that breaking her silence would lead to her sister's death. Phoebe's abused corpse was found shortly afterward, and a local sex offender, Lazarus Abbott, was executed after Tess described the abductor and pointed to him in court. Two decades later, DNA evidence exonerates Abbott, and Tess becomes vilified in Abbott's New Hampshire home town, leading her to some awkward amateur sleuthing to uncover the truth. Her implausible relationship with Ben Ramsey, the attorney representing the Abbott family, fails to distract readers from identifying Phoebe's real killer, hidden by only a scant handful of red herrings. (Sept.)