Her Scorched Bones (en Inglés) - Fiona Tarr

Missing motive for murder...

Constable Jenny Williams took a job in a remote opal mining town for answers. When the case surrounding her missing cousin goes cold, she embraces an invitation to party with the locals. But the night is cut short when the live music event turns into a crowded crime scene.

A high-pitched scream and the smell of burning flesh has left a woman burned to death. No one saw the perpetrator, not even Jenny. Now it's her job to catch the psychopath before they kill again. With no ID, no witnesses and no one coming forward who knows the woman, her case has no leads - not even a motive.

Until the victim's best friend wanders into the police station, nearly three days later.