From New York Times and #1 international bestselling author Linwood Barclay comes the jaw-dropping finale of the Promise Falls Trilogy.

It's May 23, and small town Promise Falls finds itself in the midst of a full-blown catastrophe with dozens dead from a flu-like virus. Investigator Cal Weaver quickly zeros in on mass poisoning and a tainted water supply.

Meanwhile, a college student has been murdered, and Detective Barry Duckworth recognizes a killer's handiwork from the unsolved homicides of two women in town. Suddenly, the strange events from the last month start to add up. ... Bloody mannequins in car "23" of an abandoned Ferris wheel ... a fiery, out-of-control bus with "23" on the back ... "23" on the hoodie of a man accused of assault.

The motive for hurting the people of this town points to the number 23—and working out why will bring Duckworth closer to death than ever before.

"There's definitely something rotten in Promise Falls. In The Twenty-Three, the riveting final installment of the Promise Falls trilogy, the story comes to a frightful and fitting conclusion. Nothing is more satisfying than tucking into a new Linwood Barclay novel, and this is one we've all been waiting for."—Shari Lapena, New York Times bestselling author of The Couple Next Door