Dexter and Harrison find themselves closer than ever over Christmas break, bringing father and son into the crosshairs of a serial killer; Angela starts to wonder if Iron Lake is not the safe place she always thought it was.
Someone has discovered Jim Lindsay's secret identity, leading Dexter to realize that he might not be the only serial killer in town. Meanwhile Harrison spirals out of control during a wrestling match.
Dexter fights for his life in the woods, leading to a confrontation in an abandoned summer camp; Harrison finds himself torn between two father figures who can lead him down two different paths; Angela makes some disturbing discoveries.
Dexter's method of protecting his son from drugs unleashes his Dark Passenger; Angela and Molly's New York City trip leaves them wondering about a well-respected member of the community.
Dexter turns from predator to protector out of concern that a serial killer has set its sights on someone he cares deeply about. Angela arrests someone who may be the culprit of a cold case. Harrison turns to a very dangerous person.
Alguien cercano a Dexter logra encontrarlo. Mientras tanto, Dexter se pregunta si puede suprimir los impusos asesinos de su Pasajero Oscuro cuando un fanfarrón local se comporta temerariamente.
El padre de la persona a la que mató Dexter hace un anuncio sorprendente. Mientras tanto, Harrison es considerado un héroe para toda la ciudad después de verse involucrado en un grave incidente en la escuela.
Dexter and Harrison try to live a normal life in a place that they have discovered is not as normal as they thought it was. Will they live happily ever after, despite all the threats coming their way?
