For Newfoundland writer Russell Wangersky, your grocery list says a lot about you. In his creepy psychological thriller Walt, the title character, a misanthropic and hyper-observant grocery-store cleaner, collects discarded lists and uses them in increasingly sinister ways.

In his own words, Wangersky opens up about the collection that spawned the novel... and — let's be honest — a bunch of other pretty disturbing influences he picked up on the way.

"I started collecting real grocery lists over two years ago. I went to the store, pulled out a cart, and someone had left their list behind. And it was so much like a tiny poem that I started looking at the list and thinking, what happened if you drew a story out of that list? I collected more and more and now have several hundred. I used them to structure Walt; they appear at the beginning of chapters. But now, even though the book's done, I haven't yet been able to stop collecting them.

"It's strange, because it's such a personal part of people's lives — both the lists themselves and what the lists are written on. I've got them written on everything from addressed mail to MasterCard statements to mortgage statements. I have a list written on the helicopter safety manifest listing all the passengers' names on that helicopter. It is absolutely fascinating what people are willing to reveal and throw away. When you see them all on different coloured paper and different handwriting, some of them run over by the carts and left out in the water, you look at them and you go, 'This is a pretty creepy pile of stuff.'"

"Parts of Walt deal with cabins in remote parts of the province. It's something I've experienced myself when I go on fishing trips: You go up to a cabin that's barely standing or part of the roof is caved in and the windows are broken out, and you look in and maybe you go in, and the floor's gone, and there's something about the way they have ended in process. No one has cleaned them out, all that's left is wet dirty clothes and sheets and canned goods, and pots in the sink, and you can't help but think that you're not alone. And you're not alone. You're there with someone's distinct set of memories. And they've stopped coming and you have no idea why."

"My day job is in journalism — right now, I'm a columnist for 27 Atlantic Canadian papers. I wrote Walt largely on the fringes of my workday, mostly evenings and weekends. I don't know that I'd ever be one of those writers who actually could write full time at fiction or nonfiction. I've been on book leave before, and I find that usually by about 2 p.m. I'm watching trashy TV and eating frozen berries and milk, and eventually that would be all I was writing about too. 'Oh look, it's the guy in his bathrobe eating frozen berries and sitting on the couch watching reruns of crime shows.' So for me, having work and being able to get out and into it keeps me involved in people and stories and life. And that keeps me writing as well."

"I don't know if any of the music I was listening to informed the book, but the act of listening to it definitely did. Often I'd listen to a series of things and end up at the same place, with something abrasively loud. My Chemical Romance, Green Day, also played very, very loudly on headphones, which has its own terror when you're writing a book that could be seen as quite scary, and then someone comes down into your office and you see them only in the reflection of the inside of your glasses. I have been known to pull the speakers off the computer stand onto the floor and knock over my chair while essentially reeling in terror from myself."