Man With an Axe — Jon A. Jackson

“The toughest, most darkly comic, consistently superior American procedural on the market” takes on the greatest mystery of all: the death of Jimmy Hoffa (Booklist).
 
When an eager young historian asks Detroit police detective “Fang” Mulheisen for the real story of Grootka -- his legendary law-enforcement mentor -- the question leads him to uncover his late friend's notebooks. And with them, Mulheisen may also have stumbled upon the answer to one of the biggest unanswered questions in American history . . . 
 
What happened to Jimmy Hoffa?
 
The notebooks tell an incredible story in which the supposedly late labor leader was, in fact, about to meet his end when he was rescued by a gifted musician and spirited into hiding in the wilderness of northern Michigan. More than that, the past Grootka describes may be related to a deadly mystery in present-day Detroit.
 
With this action-packed novel spanning decades of cops and criminals, “Jackson remains a master of irreverent, hard-boiled comedy” (Publishers Weekly).