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Before he plays Harry Potter's mentor Dumbledore, John Lithgow is returning to his most demented character in Dexter: Resurrection
Arthur Mitchell, AKA The Trinity Killer, appeared in Dexter season 4. And yeah, if you're familiar with how that season ends, we have the same question you do...

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The JK Rowlingness of it all aside, Dumbledore is one of the kindest, noblest characters in modern fantasy literature. It makes sense that Warner Bros. has cast John Lithgow in the upcoming Harry Potter series; the Third Rock from the Sun and Harry and The Hendersons actor has proven that he can do "gentle strength." And yet, there's a truly despicable character in Lithgow's repertoire, one that he'll return to before donning the robes of Hogwarts's headmaster.
According to reports, Lithgow will reprise his role of Arthur Mitchell, AKA the Trinity Killer, in Dexter: Resurrection.
The story comes from Deadline, who broke the news of Lithgow's return to the child-minded serial killer that he first portrayed in Dexter, season 4. In case you haven't kept up with the show, Trinity is usually considered by fans to be the series' best villain, and his arc the best season of the show.
Lithgow's Trinity Killer was given that moniker because of his pattern of killing in threes, a psycopathic condition that goes back to the character's disturbed childhood. As Trinity, Lithgow gave a performance that was disturbing in its range - at some points, Arthur would act as a common-sense, charitable family man, then a violent and depraved killer, then As a fan who was watching the show as it came out, Lithgow's portrayal of his character's warped "innocence" sent chills down my spine.
Which is why it was so satisfying when Dexter killed him.
Yes, the monster that Lithgow played in Dexter season 4 ends up a victim of the titular serial-killing forensics investigator. So how the hell is he going to be reprising the role in Showtime's upcoming sequel series Resurrection? Well, it could be in flashback, as we saw him in Dexter: New Blood, but officially, we just don't know. We do know that he won't be alone in his miraculous comeback, however. Jimmy Smits, who played Miguel Prado in Dexter season 3 and also wound up on Mr. Morgan's killtable, is set to reprise his role as well.
Who knows? Maybe just like Dumbledore, the Trinity Killer will have discovered some power over Death. And unlike the only man Voldemort fears, our boy Arthur wouldn't be so careful about using that power.
Dexter, its sequel series New Blood, and its prequel series Original Sin, are all streaming on Showtime.
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