In the most distilled terms, Heather O’Neill’s sophomore novel tells the story of the Tremblay family of Montreal. The family consists of 19-year-old twins Nouschka and Nicolas; their once famous and now dissolute folk-singer father, Étienne, a faded Quebecois cultural treasure; and their slightly mad grandfather Loulou. As the 1995 referendum approaches, Nouschka makes an innocent decision that accelerates her family’s descent into chaos. The story, while essential, is secondary to the fantastical atmosphere O’Neill creates. It’s a carnival ride of a book – bright, slightly disorienting, and incredibly fun. O’Neill knows just how far to tip you over without letting you fall.

This is a book in which more is more: easily half a dozen similes (many of them involving cats) crowd onto any given page, in much the same way the characters crowd into small apartments and nose their way into one another’s business. It is full to bursting – a choice on the author’s part that shows not only confidence but a heightened sense of play and vibrancy.

O’Neill could be considered the delightfully bizarre lovechild of Hugh MacLennan and Miranda July – if she weren’t so entirely herself. Her Montreal is a sexy, surreal landscape of laundromats, stray cats, and biker gangs; it is simultaneously magical and filthy, gorgeous and corrupt. The novel’s language – celebratory, cocky, dangerous, and desperate – reflects the atmosphere these characters live in. It’s common enough to say that a city becomes a character in a novel (and, indeed, Montreal is an irresistible, nicotine-stained presence here), but O’Neill’s very language becomes a character: unapologetic, slightly mad, impossible to ignore.

What elevates The Girl Who Was Saturday Night from merely clever to literary powerhouse are its roots in the culture and experience of francophone Montreal. While O’Neill’s imagistic fireworks are breathtaking, they would be unanchored without the Tremblays’ genuine (and tormented) love for the city, its languages, and its people. The swirling festival of literary devices exists as a way of transporting the reader into a mindset and emotional reality otherwise inaccessible to outsiders. It is a virtuoso accomplishment in both writing and cultural conversation. O’Neill employs magic realism as an avenue to emotional realism, and it packs a wallop.

This strange, beautiful book should be read by cat lovers, Canadians, the lovelorn, and the obsessed – basically, that is, by everyone.