The BAU investigates an urban vampire who kidnaps his victims at night and holds them underground in the sewer system; Reid makes a difficult decision in prison.

Following an explosive face-to-face encounter with Everett Lynch, a.k.a. “The Chameleon,” Dr. Reid suffers from a brain injury and, while experiencing hallucinations, is visited by ghosts from his past. Also, the BAU makes a shocking discovery about Lynch that affects Rossi personally, and the entire BAU team comes together to celebrate Rossi’s retirement.