Millie Driscoll and Trevor Ford have been best friends since they met at The Academy. Being able to join the FBI's Behavioral Analysis Unit together was a dream come true. When the BAU gets wind of a serial killer terrorizing Calico Rock, New Mexico, Millie thinks going to a new city will be just what she needs to kickstart her love life. After all, it worked for her friend Matthew when they went to Iowa. Trevor knows Millie considers him her best friend, which is why he would never jeopardize that relationship by revealing the more than friendly feelings he's been harboring since they met.

While in Calico Rock, Millie meets Sebastian Sable, a sexy, mysterious man who she shares a mutual attraction to. Millie and Sebastian's relationship develops from the possibility of a hot one night stand to something more serious as the search for the serial killer intensifies. With every new piece of evidence pointing to Millie being the next victim, and the killer always three steps ahead of them, the BAU begins to wonder if they will be able to catch him in time, and Trevor wonders if his tech skills will be enough to save his best friend from a stone cold killer, and the possibility of her heart being broken by a man he doesn't quite trust.