Kathleen George, a theater professor at the University of Pittsburgh, definitely knows this town and where to dine in it. Local settings and restaurants -- from Alexander's for dinner to Lindo's for breakfast -- are woven throughout her latest.

Showing characters as they meet and what they eat and drink is the kind of detail that makes them more three-dimensional, like people you know.

It also hints at the characters' relationships, such as when a police commander savors a sandwich made by his thoughtful and patient wife.

But "Afterimage" isn't a travelogue or a dining guide about Pittsburgh. It is first and foremost a thriller.

It opens with the brutal stabbing of a woman in her Regent Square home. On the case is the handsome and dedicated Cmdr. Richard Christie of the Pittsburgh homicide squad, who was also in George's novels "Fallen" and "Taken."

Along for the ride is Colleen Greer, a rookie detective eager to please the boss. The investigation takes on another meaning for her when she realizes she knew the victim -- she is the estranged wife of the head of the counseling center where Greer was a therapist before she got into police work.

Two days later a young girl is found strangled and dropped in West Park. The girl is someone else Greer has been acquainted with, but do the victims have anything else in common?

Images begin to pop into Greer's mind, and she wonders if she's straining for a connection between the murders or if her imagination is just in overdrive. Will a hunch lead her into danger or career suicide?

Halfway through the book George reveals the killer, a bit jarringly, and the main question changes from "who" to "why." In between the twists and turns, George digs into Greer's personal life and past, showing what makes this female cop tick and what she distrusts about a suspect. Discussion of pedophilia, alcoholism and family ties adds more dimension to the story.

These all lead to a tumultuous ending that is gripping yet unsatisfying in a way. You've spent all this time getting to know the heroes and feel sympathy and respect toward them, and that's what makes their final act surprising and disappointing.

But George's characters are human, after all, and you can imagine such deeds happening in real life. Not all endings are neat and clean.