Monday's episode of The Passage filled in the backstory of Shauna Babcock (Brianne Howey), a death row inmate who became one of the vampiric "virals" at Project Noah. She was transformed into a mute blood-drinker with psychic powers as the result of a test of the virus that gives people regenerative powers but turns them into monsters. But thanks to the psychic projections she sent into the mind of Agent Clark Richards (Vincent Piazza), we also found out there's still plenty of humanity left in Shauna. She was able to convince him to spare her life after he saw the sad story of how she ended up on death row.

"It was a roller coaster," Howey said of shooting the episode. "The writing is incredible. It's all there on the page. All the subtext, all the topics that we knew would be uncomfortable to shoot and talk about, the writers handled in such a beautiful way."

In the previous episode, Babcock killed a guard who had been taunting her. "That Should Have Never Happened You" picked up with the staff of Project Noah trying to figure out what to do with her. Richards was of the opinion that she should be put down, and volunteered to see the task through. Richards and Babcock have a history, though: They met when she arrived at Project Noah, when he saved her from some guards who were assaulting her. He was the first person to treat her like a person she'd encountered in years. He lied to her, though, when he told her that whatever they were about to do to her wouldn't hurt. Plus we've seen Babcock visit him in his dreams, telling him that they were supposed to be together. So there was something personal about his decision, and something equally personal about her decision to show him where she came from. (This was encouraged by Fanning [Jamie McShane], who's Patient Zero and the most powerful viral and the only other viral with psychic powers, as far as we know.)

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What she showed him was a lifetime of abuse and neglect by her mother and her stepfather. He sexually abused her when she was a child and stole the money she had saved up to get away as as adult, and her mother knew and didn't do anything about it. "You could have said no," she said to her daughter. So Shauna stabbed them both to death, which put her on the path that sent her to death row and eventually to Project Noah. Shauna did what she was convicted of, but Richards (and the audience) are made to understand and empathize with why she did it. "Everybody in that girl's life let her down," Richards said just before he made the call to stop her execution. "I presented myself as someone who wouldn't."

Brianne Howey, The Passage Photo: Erika Doss / FOX.

There's more to Richards and Babcock's backstory, which we'll see at a later date, Howey promises. "There's definitely more in store," she said. "It was something that I didn't necessarily know was going to come, either. So when we got that episode, I was thrilled. The Shauna-Clark backstory is beautiful. I love it. I'm so excited for everyone to see it. There's a lot more that bonds them. He means a lot to Shauna. There's only so many people about Project Noah to bond with, and Clark was hers."

We're also going to see more of Babcock's psychic abilities, of which we've only scratched the surface. As Babcock overcomes the idea beaten into her by her mother that her life is a series of things that happen to her, she'll start to embrace what she's capable of. "Through the course of the season she definitely finds her agency," Howey said, "And she kind of takes more control over her life." Which will be good for her, but maybe not so good for people who aren't vampires.

Shauna Babcock is based on a character from the novel The Passage named Giles Babcock. His backstory is very similar, and he goes on to escape from Project Noah and psychically control many other virals and humans. Howey said that both Babcocks have a similar feel. "Babcock in the book — and this is what really struck me — has this kind of boundless presence," she said. "He's kind of untouchable. And when someone has the ability to get in your head and you have zero control, that's terrifying. So that's all still there."

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The Passage's pilot went through extensive reshoots and the plan for Season 1 was changed to cover a smaller, more focused time period than Justin Cronin's sprawling novel. Howey said that this didn't change Babcock's arc, but it did afford more time to fill in backstory with episodes like this. What changed the most about Babcock was her and the other virals' appearance.

Howey said the original character design was closer to what's described in the books, which readers have compared to big, green wingless gargoyles. "They looked less human," said Howey. "But it was important, because they don't have voices, to be able to see the virals as human. The whole show is about humanity. And if we can't see the humanity in these virals then there's no show. So it was important to be able to see who they really were. And we couldn't see them as much before."

This episode made us unable to see Shauna Babcock as anything but human. The challenge for the show going forward will be to keep us relating to Babcock as she goes to darker places.

The Passage airs Mondays at 9/8c on Fox. It's available to stream on Hulu.