Camilla Lackberg proves why she's called Sweden's "queen of crime" in her superb seventh novel set in the coastal town of Fjallbacka. "The Lost Boy" combines a gripping police procedural with a ghost story while poignantly delving into the devastating effects of grief, especially among mothers.

The joy that police detective Patrik Hedstrom and his wife, Erica, a true-crime writer, feel over the recent birth of their twin sons is balanced by a recent horrific car accident in which their infant nephew was killed. In addition, Patrik ended up in the hospital at the same time Erica was giving birth.

Back on the job after sick leave, Patrik and his fellow detectives investigate the murder of Mats Sverin, Fjallbacka's finance officer who was instrumental in restoring a dilapidated hotel into a ritzy spa that surely will attract high-end tourists to the town. Mats was well-liked by his colleagues and the town's residents, and doted on by his loving parents. His life recently had become complicated with the reappearance of his high school girlfriend, Nathalie Wester, and her 5-year-old son, Sam. Nathalie had fled to the area in the middle of the night, returning to the nearby remote island Graskar where she grew up. Located just outside Fjallbacka, the island was nicknamed Ghost Isle because of the legend that those who die on the island remain there in spirit. Nathalie believes in those ghosts - she talked with them when she was a child - and, now, she again finds comfort in them.

Delving into the intricacies of police work, Lackberg also turns "The Lost Boy" into a psychological thriller that digs deep into each character's psyche. While the shadowy ghosts permeate the story, Lackberg keeps this supernatural aspect akin to those in the gothic masterpiece "The Turn of the Screw." Are the ghosts real or are they in the character's mind?