Murderer in Shadow. DCI Arthur Ravyn British Murder Mysteries, #4

The long-abandoned Stryker Farm was a cursed place, and everyone in Knight's Crossing shunned it, even the village's most potent magicians. Young Dale Stryker butchered his entire family, including the fearsome Wizard Ezekiel, then vanished. Thirty years later, a lost boy opens a cold case considered closed. DCI Ravyn and DS Stark find themselves searching for a long-hidden foe in a secretive village wary of strangers, where magic, both light and dark, is part of everyday life...and death.