Historical Background:

Boston, 1974, is a city simmering with unrest sparked by the desegregation crisis in public schools. The «busing» program, intended to foster integration by shuttling black schoolchildren to predominantly white schools and vice versa, has ignited fierce opposition. Though well-intentioned, the backlash is vitriolic, racist, and violent. Amidst this turmoil, the underworld’s reins are held tightly by mob boss James «Whitey» Bulger (renamed to «Marty Butler» in the novel), adding another dark chapter to Boston's storied past.

Plot:

In the eye of this storm, the life of single mother Mary Pat Fennessy is upended as she searches for her missing teenage daughter. Jules has vanished shortly before what was supposed to be her first day at a predominantly black school. Meanwhile, Augustus «Auggie» Williamson, a young black man, is found dead, and eyewitnesses claim he was chased down by four white youths… Was Jules one of the pursuers?

Dennis Lehane takes us to a focal point of American history, weaving a narrative ripe with racially charged animosity, police brutality, and mob rule. People like Mary, who scrape by on the margins, seeing no glimmer of hope in their joyless existence, are looking for someone to blame. A scapegoat that allows them to say, «It's not my fault, it's because of those blacks…»
    
Lehane uses this historically charged setting to explore profound societal questions. His Irish-Bostonian roots lend a raw authenticity to the story, particularly to its protagonist: Mary, who is also of Irish descent.
    
Characters:

Mary is indeed a protagonist readers can empathize with, despite her character flaws and profound prejudice. She has lost much in her life: a husband killed by gang violence, a son who survived Vietnam only to succumb to heroin. And now, her daughter's disappearance is just too much to bear… As she seeks solace within her community, she comes to a stark realization about her own blindness to its toxic, volatile undercurrents.

Mary doesn’t see herself as racist, yet occasionally catches herself harboring thoughts that whisper of prejudice – especially when she feels powerless, scared, or lost. But those are only fleeting thoughts, right? She is good friends with her black colleague, Dreamy, isn't she? It's dreadful that it was Dreamy’s son Auggie who was found dead… Found dead where her daughter was last seen…

Mary's perceived bond with «the blacks» is, in truth, a fragile facade that helps her feel better, though she doesn't take concrete actions to show support or solidarity. Amid her pain and fear, however, Mary does experience inner growth, questioning the racial prejudices of her community – and her own. She is a tough woman who now turns that toughness on herself, refusing to excuse her her own bigotry any longer.

Dennis Lehane has me empathize with this chain-smoking, embittered little woman, who tries to claw her way out of the morass she only now recognizes as such. She dares to prioritize her daughter over the community’s code of silence, yet finds herself left with nothing but a thirst for vengeance.

Lehane’s portrayal of other characters also reveals a keen sensitivity to their complex, often conflicted inner lives. To name only one, there's Detective Bobby Coyne: Like Mary, he is fundamentally broken by the toils of life.But unlike her, he still sees reasons to continue living, to do better and allow fleeting moments of mercy, even if they feel as futile as drops on a hot stone.

(As the title suggests, small mercies are a recurring motif throughout the novel; delving into the pivotal one would spoil the story’s most significant revelation.)

Suspense:

While not a conventional thriller, the skillful intertwining of personal drama and political strife still creates creates an unyielding tension that grips the reader.

Writing Style:

Lehane’s prose is sharp and potent, capturing the era’s social tensions on every page. His dialogues breathe life into multifaceted characters, making their flawed views more comprehensible within their personal narratives and the broader social circumstances.Racism and hatred are shown as ingrained parts of the societal landscape.

Conclusion:

Lehane walks a tightrope with this novel, balancing a thrilling narrative with profound criticism of historical and social issues. He portrays hatred as a pervasive system that directs cruelty and violence against outsiders, yet also sacrifices friends and neighbors to an unspoken code of compliance.This narrative is compelling, often distressing, and deeply tragic for more than one character. In my eyes, this is definitely not a light read, but a profound experience that I highly recommend.