Death's Jest-Book by Reginald Hill

Bestselling and Diamond Dagger award-winning mystery writer Reginald Hill sets up a battle of wills between determined cops Andy Dalziel and DCI Peter Pascoe and an elusive and ingenious villain in a “dazzling” novel of psychological suspense (New York Times Book Review).

Three times Yorkshire policeman Peter Pascoe has wrongly accused ex-con Franny Roote of a crime, only to have Roote walk free. Now Roote is sending out strange and threatening letters and Pascoe fears there is worse to come. This time he’s determined to get his man.

Meanwhile, Pascoe’s colleague Edgar Wield rides to the rescue of a boy in danger and in return, the boy tips him off about the heist of a priceless treasure. Soon Wield is torn between protecting the lad and doing his duty.

Over all this activity broods the huge form of Detective Superintendent Andy Dalziel. As trouble builds, Dalziel discovers that omniscience can be more trouble than it’s worth.