André Alexis’s new novel – Book 3 in a projected five-book sequence – takes place in a Toronto that will be instantly recognizable to anybody who has walked the same streets and slumped in the same corner booths as its characters. The very first line name-checks both the west-end blues bar the Green Dolphin and the mansions of the Bridle Path. The Trinidad-born author of last year’s Scotiabank Giller Prize winner, Fifteen Dogs, is doing more than simply shouting out his adopted hometown, however. By juxtaposing one of the city’s most pungently unreconstructed neighborhoods with one of its richest, he’s acknowledging the vast social and economic divides at the heart of Toronto life – and foreshadowing a story in which one of the have-nots seizes a unique opportunity to line his pockets.

That would be Tancred Palmieri, a 25-year-old French-African thief who lives in Parkdale, where he’s friendly – if not philosophically sympatico – with a host of unsavoury neighbours. As the book opens, Tancred, who is eking out a living, has befriended Willow Azarian, an addled, fiftysomething junkie whose bedraggled appearance belies her old-money birthright. Unlike the other members of her family, who all live closer to the city centre, Willow doesn’t wear her wealth on her sleeve, favouring instead a ragged wardrobe that makes her look “like an outpatient from the Queen Street Mental.”

Alexis sets up Tancred and Willow as a study in contrasts: male/female; young/old; white/black; poor/rich. He also makes it clear that the two are kindred spirits. They’re both poetic souls, attuned to suffering and drawn to mysteries, and the older woman is sitting on a doozy. Willow explains that her late father bequeathed to her and her four siblings a series of baroque, bespoke gifts – hand-crafted objects ranging from a Japanese screen to an elaborately mounted painting. She believes that each of these personalized creations contains some hint to the location of an even larger inheritance, and that only by putting these clues together can the fortune be found. She asks Tancred to steal these gifts, one by one, and tease out their respective secrets.

The Hidden Keys gets going so quickly that the unlikeliness of the set-up doesn’t really register, and Alexis shows that Willow, who isn’t long for this world, has her reasons for kick-starting such a bizarre arrangement. “Even if you are a thief, you’ve got principles,” she tells Tancred. The stoic pro with a good heart is a bit of a cliché – endlessly reinforced in genre fiction and films – but The Hidden Keys puts an interesting spin on the archetype. Tancred’s principles, like anybody else’s, are contingent on circumstance, and Alexis is a resourceful enough writer to push his protagonist beyond simple, ineffable goodness. There’s a mercenary aspect to Tancred’s quest, as well as an in-built opportunity to access – and, in doing so, stealthily attack – avatars of (white, establishment) privilege even as he’s driven consciously by the desire to honour his friend.

Though Tancred contains multitudes, one of Alexis’s best tricks involves diverging from his hero’s point of view to introduce a whole host of peripheral figures – including a vicious drug dealer and a cop who has known Tancred since childhood – whose inner lives are more fully realized than seems necessary at first. Nobody is a mere archetype in Alexis’s universe, and far from digressions (or generic concessions), these subplots suggest the humane, egalitarian sensibility of a writer who’s reluctant to simply instrumentalize his characters.

As its title suggests, The Hidden Keys unfolds as an interpretive exercise for the reader, who can’t help but try to connect the dots – the sprawling constellations of numbers, ciphers, codes, and symbols swirling around the objects – along with Tancred, while simultaneously thrilling to the precisely described episodes in which he filches the treasures. (In one seriocomic set piece, Tancred’s associate is accidentally knocked unconscious, turning a heist into a desperate and slapdash rescue operation). At times, the set-ups and situations seem to come straight out of a Hardy Boys novel, but described in the plain, direct style of a parable or a fairy tale. Despite his love of incident and intrigue, Alexis is a minimalist who never lets language get in the way of plot or character.

As is apparent right from that Queen Street West opener, it’s Alexis’s commitment to specificity that wins out. He dispels the potential preciousness of his project by grounding it in simple, physical descriptions tied to a time and place he knows well. This enchanted everyday texture is unique, and accounts for why is the rare kind of mystery novel that actually starts to feel more plausible as it barrels along. The truths it unveils at the end of its byzantine trajectory are old durables that bear repeating: the pursuit of a goal is always more satisfying than attaining it, and virtue doesn’t have to be its own reward to be worth something in the end.