Season 5 delves deeper into the personal lives of the BAU team and also brings back many of the show's most feared killers. Hotch takes a brief leave of absence, and Rossi investigates a case in his hometown. Some of the more gruesome crimes involve a killer who keeps the eyes of his victims as a souvenir and a woman who kills to satisfy a rather childish obsession. Rocker Gavin Rossdale guest stars as a performer suspected of murder, and in the show's 100th episode, C. Thomas Howell and D.B. Sweeney return in their respective roles as "The Reaper" and US Marshall Kassmeyer as the BAU team race to help Hotchner save his family before it's too late.