It’s two weeks until Christmas, but not all the lights twinkling in Los Angeles’ Baldwin Hills are cheery.

There’s a firebug about.

But the fire that Los Angeles Police Department (LAPD) Detective Elouise “Lou” Norton and her partner, Colin Taggert, are called out to early one morning is no ordinary case of arson.

When the fire is controlled and investigators can enter the house, they find the corpses of a teenage boy, an adult woman and a young child inside. The woman is holding a rosary in one hand, a gun in another and cradling the girl.

The woman had made the 911 call saying “(something) trying to kill me.” The gun had been purchased just a week earlier. Her car was packed with suitcases containing clothes for herself, the boy and the little girl.

Then as the fire department is cleaning up, the husband, Christopher Chatman, comes storming to a stop in the driveway and tries to enter the house to save his family. As firemen stop him from entering the dangerous building, he’s injured and taken to the hospital.

When Lou and Colin interview neighbors, they describe an idyllic, successful, middle-class black family living the dream. But the deeper Lou probes, the darker and more contradictory the picture gets. The Chatmans’ best friends, Benjamin and Sarah Oliver, make the picture even murkier.

And the question remains: Who set the fire — and how did they do it?

This is a wonderfully challenging mystery with no easy answers. Lou Norton is a great character with a dark history and a troubled marriage. Her partner is a white police officer transplanted from Colorado Springs and not entirely up to speed on L.A.’s diverse cultures. The dialog is snappy and the Los Angeles backdrop for this story vividly rendered.