Cassie Hobbes joined the FBI's Naturals program at seventeen because she had an incredible ability to read people.

Since then, Cassie, fellow profiler Dean, emotion-reader Michael, lie-detector Lia, and statistical genius Sloane have caught serial killers, outsmarted masterminds, and saved countless lives. Now, eight months after the most twisted, traumatizing case of their lives and still dealing with the psychological fall-out, the Naturals decide to take on a joyful mission for once: playing matchmaker. With Christmas fast approaching, how hard could it be for an emotion-reader, a deception detector, two profilers, and a statistician armed with a wealth of data on romantic relationships to secure a happily ever after for two people who are already very obviously in love? Turns out ...very. Because to bring their FBI mentors back together, the Naturals will first have to solve the mystery of why Special Agent Veronica Sterling can't let herself have the very thing she wants the most. Profiling a profiler is tricky business, and it soon becomes clear that to solve this mystery, the Naturals need to uncover the past.

Add in a puzzling series of interconnected crime scenes, an UNSUB with a fondness for snow, and a cold case on the verge of heating up, and it's shaping up to be a killer Christmas.