Solitude Creek by Jeffrey Deaver 

When an interrogation goes badly wrong, California Bureau of Investigation Agent Kathryn Dance finds herself busted back to rookie.

Her new assignment: routine insurance checks after a roadhouse fire. But the evidence show that the fire was no tragic accident.

A highly trained expert in body language, Dance’s most deadly weapon is her instinct, and they can’t take that away from her. Protocol won’t stop her doing everything in her power to take down the perpetrator.

Someone out there is using the panic of crowds to kill, and Dance must find out who, before he strikes again…