Mercy Killing

After suffering a horrible tragedy, hitman Jules Hallenbeck goes on the run, and it's up to Del Copeland to find him. 
Del's a cop, but he's not about to bring Jules in. 
In fact, his loyalties lie more with Neville Ludlow, the crime boss who employed Jules, than the badge he wears. 
And Neville wants Jules dead. But it'll be up to Del to pull the trigger. 
All this is complicated by a seemingly-innocent accountant of Neville's, Seraphina Lang, who Del soon discovers knows more than she's letting on...