Unless you’ve been in a trance (that only looks like a coma) for a lengthy period of time, you know that Netflix has released most of Stranger Things‘ fifth season, with the series finale arriving December 31 to hopefully answer all our lingering questions. But one aspect of the Netflix show we’re now much better informed about is its big bad, Vecna. Played by Jamie Campbell Bower, he was introduced in season four—but season five has shown us just how complex this man-turned-monster really is.

For starters, he now has a third identity to go with the tendril-and-teeth creature that is Vecna and his onetime human form, Henry Creel—the angry guy storming around in the blood-spattered orderly uniform. Season five introduced Mr. Whatsit, a seemingly gentle protector lifted from A Wrinkle in Time and used to manipulate the group of kids Vecna requires to put his ultimate plan in motion.

Speaking to Deadline, Bower reflected on what it’s been like playing Vecna as the character has become more complex.

“Towards the end of filming the Henry portion of season four, Matt and Ross [Duffer] were like, ‘This has been amazing. We were always going to bring you back as Vecna, but now we feel like we should bring you back more as you.’ and I was just like, ‘Cool. Sounds great. Whatever you guys want,'” Bower recalled. “So, with regards to the story arc, none of it was pitched to me, and I think it was … something that sort of developed in the in-between time.”

Once Bower knew what was in store, figuring out how to play multiple personas contained in one character came down to finding the right emotional tone, as well as some movement training.

“Where I got to with Henry at the end of [season four] was the way in which I wanted to be bringing him back when we saw him again. It was in that emotional space,” he explained. “Having lived in Mr. Whatsit already in season five, there is a difference for me between them, subtle though it may be, there is a difference. So yes, there are emotional differences and difficulties, but also physical [ones]. That particular moment, the physicality of that was something that we worked on with, actually, with somebody who works in the video game space, and using things called nodes, which are like particular moments that you strike and that you’ll come back to. So the shift between Whatsit and Henry was something that we worked on off-set prior to shooting it.”

And then, of course, there’s Vecna—the most evil; he’s fully monstrous and removed from humanity in that “it’s virtually impossible [for him to feel] anything that feels like love,” Bower said. Still, the actor’s still grappling with what he thinks audiences will take away from his multi-layered character once the dust settles.

“So much of this character is based on the idea of loneliness [and] the idea of salvation. I had to fall in love, and I did fall in love with Henry Creel. I had to want to protect him,” he said. “I had to want to nurture him and love him, because that’s my duty as the person that’s playing him. I have to understand him, and I don’t know how it feels to be a viewer, yet, watching that from afar, I don’t know. I’d have to give myself another six months to truly be able to absorb that.”

The Stranger Things finale arrives December 31 on Netflix.

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