In her 2015 novel, “The Unquiet Dead,” Ausma Zehanat Khan, former editor in chief of Muslim Girl magazine, introduced readers to the flawed but brilliant Esa Khattack. A Canadian detective of Pakistani descent, Khattack is a fascinating, complex character. He’s a fervent Muslim who finds himself in the position of investigating crimes that may tarnish the reputation of the very minority group he’s a part of.

In Khan’s new novel, “The Language of Secrets,” fellow Muslims call him “the house Arab.” His non-Muslim co-workers distrust his allegiance at every turn. Khan, who holds a PhD in international human rights law, fills this thoughtful yet suspenseful novel with fully developed Muslim and non-Muslim characters. No one is perfect, nothing is rendered in black and white, and everyone has passionate beliefs.

As she did in “The Unquiet Dead,” Khan focuses her novel on an event in the news: Islamophobia and the new millennium’s war against terrorism.

Khattack is asked to investigate the shooting death of Mohsin Dar, an undercover officer who had infiltrated a Muslim terrorism cell. He must determine whether Dar’s death was related to his police work or is something more personal. Complicating matters is that Khattack can’t risk raising the suspicion of the cell, whose activities are being monitored by INSET, Canada’s version of Homeland Security. The cell is planning a major attack in the Toronto area, and INSET needs time to determine the target and identify the participants.

(Alan Klehr)

Khattack’s investigation is thwarted by a grudge-ridden officer of the Royal Canadian Mounted Police who belittles and bullies him at every turn. Is it because Khattack is a Muslim? No matter: Khattack has a job to do.

Sgt. Rachel Getty, Khattack’s partner, goes undercover at a mosque frequented by the terror cell’s charismatic leader, Hassan Ashkouri. There she finds fervent followers of Islam as well as lost souls in search of community, including two teenagers, a Somali immigrant and a Canadian woman who buries her emotional problems behind a mask of painful piercings. Getty wonders “who in these difficult days would choose to enter the fold of Islam? It was hardly a popular choice when outrages connected to political Islam were becoming routine and mundane. Unless the message struck deep to the soul.”

“The Language of Secrets” is as much an examination of the complicated social, political and religious aspects of the war against terrorism as it is a crime procedural. It also offers readers an introduction to Arabic poetry and fascinating details about Khattack’s and Getty’s personal lives. These colorful threads complement the bigger storylines — finding Dar’s killer and stopping a cataclysmic event that’s inspired by a true story: a foiled 2006 plot to blow up Canadian Parliament.

The novel’s somber tone is lightened by Getty’s clear-eyed views. “It wasn’t enough to say that the same faith that had produced Hassan Ashkouri also had produced Esa Khattack, good and evil sketched out in broad strokes,” she thinks. Unlike some, she believes it’s more “nuanced, complex” and “difficult” than that because “something could be beautiful, humane, encompassing. Or it could be made ugly.”

Carol Memmott who lives in Virginia, also reviews books for the Chicago Tribune.

the language of secrets

By Ausma Zehanat Khan

Minotaur. 329 pp. $25.99