Carrie thinks Mr. Big is keeping her a 'secret' while Miranda discovers a sex secret about her new boyfriend. Samantha has never been discreet with anyone she's ever slept with, and Charlotte divulges her past secret love affair with a Hasidic Jew.
A series of murders in Manhattan seems random at first, then the police fear that a serial killer may be copying the crimes of another decades earlier.
A chef and his patrons are poisoned after consuming a menu item tainted with snake venom; Detective Bell's crush on a colleague leads Holmes to a realization about his relationship with Fiona.
Saul tries to track down those responsible for the attack on Langley; Quinn takes matters into his own hands; Carrie learns who her allies are; the Brody family starts therapy.
The team searches for a serial killer who kidnaps and hangs his victims.