WARNING: The following contains spoilers for Evil Season 2, Episode 8, "B Is for Brain," now streaming on Paramount+.
After months away on an expedition, Kristen's husband Andy is returning home, which means it's chaos as usual in the Bouchard household. Lynn, Lila, Lexis and Laura are decorating the room with balloons — and having a little fun with the helium in the process — while Sheryl helps with the "Welcome Home Dad" sign. Everyone is excited to see him. Well, everyone except Kristen, who sips her Trinity Whisky in peace while sitting in a hot bubble bath, seemingly dreading her husband's return.
Kristen's lack of enthusiasm does not stop her from getting it on with Andy in the bedroom. But this is not the same Kristen he left all those months ago. Her stomach is covered in cross burns (which she blames on the stove), and her sexual repertoire now includes gags (courtesy of the Sacred Trinity Monastery) and animal masks. Still, it's good, raw sex, which Andy desperately needed after spending two months atop a mountain.
The next day, Kristen, Ben and David are called to their next case. A brain mapping experiment is inducing spiritual visions in its subject and causing a significant portion of them to convert to Christianity. The Church wants to know is this is something it should be looking into further, or if it can be dismissed as a hoax.
The team interviews some of the subjects, who describe hallucinations and visions of bliss — walking down a peaceful snowy road, floating in space, hanging out with the Who drummer Keith Moon. Kristen sees this as a basic use of brain stimulation to cure depression, but David argues that the visions came first, before the physiological effects, and that spirituality cannot be induced through technology.
Ben decides to try out the machine himself. "A chance to see God and Keith Moon. Come on. How can I pass that up?" he says. Sadly, neither God nor Keith Moon make an appearance, but Ben does get a visit from his dead mother, who scolds him for abounding "everything I was for." She takes him back to his home village, only to be interrupted by a ghostly demon. Ben starts screaming and crying, prompting David and Kristen to rush in and remove him from the machine. Turns out that not everyone has positive vision, with certain subjects experiencing episodes of "grief, sadness, darkness, meaninglessness," according to the lead researcher.
Back at the church, Sister Andrea gets a visit from Leland, who has discovered that the holy water she had David use on him during his last exorcism was actually ammonia. "Here, let me show you. Put out your hand," Leland threatens her as he takes out his own bottle of the dangerous chemical. Sister Andre happily complies, lifting her hand to reveal a massive knife the size of Leland's face. "How come I've never heard of you?" a flabbergasted Leland asks. "Because I'm a nun," Sister Andrea calmly replies. Leland exits, only to run into David. "I think the Church is too hard on its nuns," he tells his spiritual advisor as he walks out. "I think they're sexy." David goes in to check on Sister Andrea, who implores him to work on his mediations. "Our enemy has become more aggressive. We need to prepare."
While putting the masks away in the closet, Andy finds hand-drawn maps of random houses hidden in a journal. He tries to confront Kristen about it while they are in line at a grocery store, but the two are interrupted by the worst demon of all — a line cutter, and a rude one at that. Andy is willing to let it go, but New Kristen is not. She grabs a bag of frozen french fires and whacks the guy in the face — shocking Andy and this recapper!
The team interviews some of the people who experienced negative visions while using the brain mapping machine. But Kristen is not deterred and decides to give it a go. However, the machine has trouble registering her, so she switches placed with David, who sees Kristen's murder of LeRoux detail for detail, right down to the ice ax, despite Kristen never telling him about any of it. In a panic, Kristen calls an emergency session with Dr. Boggs. Dr. Boggs says that David must have figured it out subconsciously through Kristen's behavior and news reports and advises her to tell him the truth. So Kristen rushes over to David's quarters in the Church, only to find Leland there, munching on David's dismembered arm as the priest-in-training cries out in pain.
Turns out, Kristen was in the machine the entire time, with David having never gone at all. Kristen rushes over to have a real meeting with Dr. Boggs. She explains everything that happened to her, including the advice Vision Dr. Boggs gave her to tell David. The real Dr. Boggs notes to Kristen that she often talks about David, even though her husband just returned home. "Reflect on what you want your life to be in this moment. If it's your husband, it's your husband. If it's David, it's David." Kristen shrugs it off as an unobtainable attraction, as David is becoming a priest and will be completely off limits to her. But Dr. Boggs says her mind may be presenting her with a challenge. "He doesn't become a priest, then he's not unobtainable."
Finally, it's David's turn to test out the machine, but, ironically, he gets nothing. He goes to see Sister Andrea about his failure. But she does not see it as failure "because your visions are not coming from regions in your brain. They're coming from God." "Start over," she advises him. "Don't use technology to rewire your brain."
David takes Sister Andrea's advise to heart and begins his basic mediations again. He also recommends the machine not be investigated further or used by the Church. But Kristen says it could be helpful to people with depression and Ben is unsure, leading to a 1-1-1 vote on its future.
Andy goes to see Sheryl about Kristen's behavior, but Sheryl blames Andy for going away for so long, forcing Kristen to "adapt" to a lifestyle without him. Sheryl then has a moment with Eddie, her creepy, wish-granting doll, which freaks Andy out. (And rightly so!) However, Sheryl's words get to him, and he confronts Kristen about her job and behavior, offering to sell their climbing business and get a real day job. Kristen refuses to believe her job with the Church is the problem, but Andy brings out the maps, which their daughters think are maps to kill people. Kristen clarifies that it is just a therapy technique. "It's a way to deal with anger. When people piss me off, I draw where they live," she fires. "But your children don't know that," Andy says, which causes Kristen to break down on the bed.
That night, Kristen quietly heads down to the kitchen. She turns on the stove, heats up her cross pendant and pushes it against her stomach, buying her a moment of peace in the flurry of pain.