What do you do once your off-her-rocker sister drives you off the road and into a lake, determined to kill your serial-killer self, only to dive in again and rescue you? That's the question Dexter faces tonight as the show's eighth and final season continues its dizzying trajectory. Check back here around 10 p.m. ET for a full recap of all the action. Just make sure to keep the lights on and the doors locked.