With Beauty Killer Gretchen Lowell locked away behind bars once again, Portland detective Archie Sheridan can finally rest.

Meanwhile, the city of Portland is in crisis. Several people have drowned in heavy rains that have flooded the Willamette River. But the medical examiner discovers that in fact the latest victim was poisoned before she went into the water—she didn’t drown. A little detective work shows that so far three of those previously thought to be accidental drownings have actually been murdered. Portland has a new serial killer on its hands, and Archie and his task force have a new case.

Meanwhile reporter Susan Ward is following up on an entirely separate mystery: the dramatic flooding has unearthed a skeleton, a man who might have died during catastrophic flooding more than sixty years ago that washed away an entire neighborhood and killed at least 15 people.

As Archie follows the bizarre trail of evidence and evil deeds to catch his killer, he has to battle the rising waters of the Willamette first.