Russell Wangersky’s oeuvre includes a pair of story collections (2006’s The Hour of Bad Decisions and 2012’s Scotiabank Giller Prize–shortlisted Whirl Away), a memoir about his experiences as a volunteer firefighter (2008’s Burning Down the House), and a Winterset Award–winning novel (2010’s The Glass Harmonica). Though his work has dealt with dark subject matter before, his new novel, about a middle-aged grocery store janitor who collects discarded shopping lists and may or may not be a murderer, is a full-on psychological thriller in the vein of John Fowles’ 1963 classic The Collector.

Set in contemporary St. John’s, and composed of diary entries, police reports, and grocery lists that occasionally read like poetry, the majority of the narrative is driven by the confessional ramblings of the eponymous janitor, who is highly observant, deceptively intelligent, and unapologetically creepy. “I hope you’re having fun at my house,” he thinks as the police search his home for evidence of his missing wife. “I hope you’re being thorough enough to burrow down through the dirty laundry piled up in the basket.”

Walt deconstructs cast-off grocery lists like a frumpy, working-class literary theorist, analyzing everything from content (“soap/bus pass/diapers”) to spelling errors and non-words (“Deorant”, “Starlae”) to the scraps of paper on which they’re written (personalized notepaper, discarded junk mail). In so doing, he attempts to worm his way into the private lives – and homes – of local shoppers. “If you’re dedicated … about collecting things,” he says, “it really doesn’t take very long to start putting the puzzle of a person’s private life together.”

The novel contains a number of chilling scenes, including a gruesome trip to an abandoned cabin while fishing out in Newfoundland’s Little Barachois River, and Wangersky does a good job keeping the reader guessing as to whether Walt is a bona fide killer, or just another garden-variety creep. But following a despicable narrator into the homes of unsuspecting women quickly becomes unsavoury for the reader, particularly when those women are flat, underdeveloped characters whose diary entries are included purely for expository reasons. “I think I have a stalker,” Alisha, Walt’s prized 25-year-old potential victim informs us. “If this keeps up, I think maybe I should go to the police or something. It’s creeping me out.”