"It All Falls Down" (William Morrow), by Sheena Kamal

Canadian author Sheena Kamal continues to show how cultural touchstones reverberate into adulthood in her intriguing look at Vancouver research assistant Nora Watts, whose major investigations are uncovering her past.

Nora technically isn't a detective, though she's worked for one, and her skills at finding people are unmatched. But Kamal's second novel delves deeper into Nora's prickly personality, shaped by her biracial background and the series of foster homes in which she was raised.

"It All Falls Down" takes Nora further away from her tenuous comfort zone. She's approached by a stranger while walking her dog, Whisper, in a park. The man claims to have served in the Marines with her late father, Samuel, while they were stationed in Lebanon. He suggests that Samuel didn't commit suicide as Nora and her sister, Lorelei, have long believed, and that his death may be related to her father's life in Detroit. Samuel was one of the many children who were part of Canada's "Sixties Scoop," in which children of indigenous background were taken from their families and put up for adoption, often to American parents. Nora's trip to Detroit also yields a link to her mother, who left when she and Lorelei were toddlers. With no photographs, Nora doesn't know what her mother looked like, or what her background was.

Back in Vancouver, private investigator Jon Brazuca, with whom Nora has a fractured relationship, is hired to investigate the drug overdose of a billionaire's pregnant mistress. Without resorting to cliches, Kamal deftly intersects the investigations of Nora and Jon in a believable plot. Both find themselves targets of killers, and neither knows why.

Kamal's affinity for the unusual, character-driven mystery excels in "It All Falls Down." While Kamal supplies plenty of action and close calls, she concentrates on the characters' motivations. Nora's background has given her a mistrust of people and made her wary of emotions. Jon, who also was her AA sponsor, has never been able to break through her wall. Her closest relationship is with Whisper.

A sense of sadness permeates the novel, from Kamal's gritty look at Detroit and unflinching look at Vancouver's neighborhoods to the flawed characters. Yet Kamal also injects a sense of hope and closure for Nora, and Whisper, and makes readers root for their future.