The Day He Left - Frederick Weisel - Bog

"A middle school teacher leaves home one morning and never arrives at his job. He leaves behind his briefcase and his phone, along with photographs of some of his female students. Across town, a detective on Santa Rosa's Violent Crimes Investigations team joins a colleague from the narcotics division as they investigate the killing of a dealer and local heroin smuggling operation. As the two cases converge in unexpected ways, secrets rise to the surface, and everyone is a suspect"--