Karen Craig of Auckland Libraries said that Aucklanders are not the only ones who enjoy reading the genre.
"It's a worldwide thing - crime thrillers in terms of any genre fiction is always number one, closely followed by romance," She said.
Craig explained that most readers liked to use their brains while following the plot, something crime novels often include.
"Crime books in particular allow you to use your brain, you're working along with the book trying to solve the mysteries, you follow along with it.
"They are usually quite ingenious, there's a lot of twists and surprises and it's a really fun read."
Sitting atop the most read books in the libraries general collection was Keyes with her romance novel The Break, behind her was Childs' 22nd installment of the Jack Reacher series - The Midnight Line.
American thriller novelist Dan Brown's book Origin was the third most popular book in the general collection this year.
The most requested fiction books for December also indicate as to what the most popular books for this year and the summer holidays will be.
The top three remains relatively the same with a slight change-of-order from most read to most requested.
Childs overtakes Keyes with Brown's novel sitting steady at third on the most requested book list.
When it comes to non-fiction, children and teen reads five cooking books make the top 10.
Chefs and authors Chelsea Winter, Dr. Libby Weaver, James Wong, Nadia Lim and Jamie Oliver all made the list with their respective reads.
Top 10 most popular books in the general collection
• The break by Marian Keyes
• The Midnight Line by Lee Child
• Origin by Dan Brown
• The Rooster Bar by John Grisham
• The Late Show by Michael Connelly
• Come Sundown by Nora Roberts
• Meet Me at Beachcomber Bay by Jill Mansell
• The Good Daughter by Karin Slaughter
• The Thirst by Jo Nesbø
• A Column of Fire by Ken Follett
Top 10 most requested fiction books in December
• The midnight line by Lee Child
• The break by Marian Keyes
• Origin by Dan Brown
• The rooster bar by John Grisham
• Two kinds of truth by Michael Connelly
• Little fires everywhere by Celeste Ng
• The late show by Michael Connelly
• A column of fire by Ken Follett
• The handmaid's tale by Margaret Atwood
• The good daughter by Karin Slaughter
Top 10 most requested 'other' books in December
• Driving to Treblinka by Diana Wichtel
• The getaway by Jeff Kinney
• Eat by Chelsea Winter
• Drawn out by Tom Scott
• What am I supposed to eat? By Dr. Libby Weaver
• How to eat better by James Wong
• Daughter of Gloriavale by Lilia Tarawa
• Let's eat by nadia Lim
• 5 ingredients by Jamie Oliver
• The choice: embrace the possible by Dr. Edith Eva Eger
