Suddenly there's a serial killer afoot in Bloomington, Minnesota, a low-crime community not accustomed to lethal assaults of this kind. Moreover, each victim is dispatched in creative fashion, involving the products of a particular advertising agency, threatening it to extinction. Darcy Austin, who discovers the first of the murder victims in that very agency, must now escape the danger she faces as a result.
Bloomington crimes-against-persons detective, Lieutenant Douglas ''Hank'' Hankenson, is challenged to track down the master assassin who challenges him back in a ''catch me if you can'' scenario.
How does the threatened advertising agency, Williams/Bailey, fit into this pattern of death? And what of the comic-book characters of Fantasy Publications that come into play as the adventure unfolds. They are fictitious are they not? And what of the mysterious vigilante known only as the Rifleman? Does he play a role in the killings, or is he pursuing a separate agenda?
Endgame concludes in spectacular fashion on Minnesota's north shore of Lake Superior at the Devil's Kettle, a spectacular, and mysterious site in its own right.