The Night Hawks (Ruth Galloway Mystery 13)

There's nothing Ruth Galloway hates more than amateur archaeologists, but when a group of them stumble upon Bronze Age artifacts alongside a dead body, she finds herself thrust into their midst—and into the crosshairs of a string of murders circling ever closer.
Ruth is back as head of archaeology at the University of North Norfolk when a group of local metal detectorists—the so-called Night Hawks—uncovers Bronze Age artifacts on the beach, alongside a recently deceased body, just washed ashore. Not long after the same detectorists uncover a murder-suicide—a scientist and his wife found at their farmhouse, long thought to be haunted by the Black Shuck, a humongous black dog, a harbinger of death. The farther DCI Nelson probes into both cases, the more intertwined they become—and the closer they circle to David Brown, the new lecturer Ruth has recently hired, who seems always to turn up wherever Ruth goes.