Starting with the opening line – “Lux was coming” – Toronto writer Catherine Bush’s second novel is peppered with interesting, albeit unusual, names. Consider the sisters Arcadia and Lux Hearne, and the Somali refugee Basra Alale (after the Iraqi city Basra, an ancient Eden of hanging gardens): their names suggest mythical paradises, the unfallen worlds where nature and humans are at one. Arcadia’s lover, Amir Barmour (an Iranian living in London, England), has a name suggesting the words armour and amour, two of the novel’s central themes.

Arcadia has fled Toronto after two men, both her lovers, fight a pistol duel over her in a ravine. In London, she begins working as a researcher in contemporary war studies.

But the past haunts her, and the plaited knots of love, violence, risk, and danger that all of the characters face, and their desire for reconciliation, self-invention, and transformation, signal the gnarled hallmarks of the human condition.

Bush is an assured, confident writer who packs bursts of lyric surprise. Much of the strongest writing is about gardens, ravines, and cities (specifically Toronto and London), and in the images of twinning: that of lovers, sisters, and that of nostalgia for the city where one grew up coupled with the fascination for one’s new home.

While there is some lounging, lolling, and pondering here, coupled with what feels like an overly pat reliance on a schematic framework, these foibles are entirely forgivable, particularly in light of the superbly written ending. The Rules of Engagement is sophisticated, brainy, and passionate; another accomplished, ambitiously high-concept novel from the author of Minus Time. Part of the pleasure of reading Bush’s second novel – at once a fast-paced literary thriller and meditation on weighty issues – lies in the frisson of seeing a writer rise splendidly to the occasion anticipated by her first novel.