We all knew John Lithgow would make an epic serial killer when it was announced he would join the cast of Dexter as Season Four's baddie. But I don't think any of us truly realized the heights (or depths) he would take his Trinity Killer character. The rubber-faced veteran has been going toe-to-toe with Dex (Michael C. Hall), and the tension is only now beginning to build. As Dexter gets closer with Trinity, he's hoping to learn from the older murderer how to completely blend in to his surroundings - camouflaging the monster within. Dexter's morbid fascination with man has prevented him from killing him thus far, even though he believes (erroneously we're guessing) that Trinity killed Lundy and shot Deborah.

In next Sunday's episode, "Road Kill," Trinity takes Dexter to his childhood home where his cycle, recreating the deaths of his sister, mother and father, began. It's the place where his sister, whose ashes he carries with him to every cycle, was first killed. Will Dexter finally understand what started Trinity's unholy ritual, or will the unhinged psychopath realize that Dexter is not who he says he is - but a fellow carrier of the Dark Passenger?

See More: Dexter | John Lithgow | Michael C. Hall | Showtime