Tropes of this episode:
- Blonde, Brunette, Redhead: Agent Reyes finds out that there is a Serial Killer at large and that his pattern consists murdering women in a set of three. Each set has a blonde, a brunette and a redhead. Redheaded Agent Scully and dark-haired Reyes get trapped in an underground garage and fear they might be his next targets.
- Breather Episode: The killer is played for drama but the rest of the episode is light and in fact, good natured especially compared to the rest of the grim Season 9.
- Numerological Motif: The whole episode deals with numerology and tries to show everything can be expressed in terms of numerological patterns.
- Serial Killer: He targets women and kills them in a set of three.
