In Texas, sometime in the '90s when Fred was preparing to move to L.A. She chats with her parents who aren't completely thrilled about her move but are still helping her pack up. Fred comes close to leaving without her stuffed bunny Feigenbaum, whom she calls "the master of chaos." She promises her parents that she'll be careful and will live a boring life. In the present, she's doing anything but - she's fighting demons with a flamethrower. Wesley helps her out and they start to get a little friendly before being joined by Angel and Spike, who had a little bad luck while fighting demons themselves.
In the science lab, Knox accepts the delivery of a sarcophagus for Fred; it's already been signed for. The next day, Gunn is in his office, singing Gilbert and Sullivan's "Three Little Maids from School are We." He spots Wesley outside the room and quickly tries to pretend that he was rapping. Gunn tells Wesley that he's happy because he and Fred are getting back together. A shocked Wesley tries to hide his disappointment, but Gunn finally admits that he was just messing with him. He reveals that everyone in the firm knows about Fred and Wesley, and Gunn is fine with their relationship.
They start discussing Lindsey, and Wesley advises Gunn to talk to Angel about him, but Gunn doesn't want to stop by his office right now.
This is because Angel and Spike are having a loud argument that seems to be important. When Wesley arrives, however, they admit that they were fighting about who would win in a fight between cavemen and astronauts.
In the science lab, Fred looks at the sarcophagus, which she doesn't think is anything sketchy. Knox tells her that he's okay with her relationship with Wesley and is fine with just working with Fred. He leaves and Fred opens the sarcophagus; an iris opens and lets out a puff of air in her face.
Spike heads back to Angel's office (noting that everyone in Accounts Receivable agrees with him that cavemen would beat astronauts), and Angel tells him that he can't put up with him anymore. He thinks that Spike should leave L.A. and be an evil-fighter somewhere else.
In the hallway, Fred and Lorne continue the cavemen vs. astronauts fight - Fred argues that the cavemen have fire, so the astronauts should be allowed to have a weapon. Wesley joins them and Fred tells him about breathing in the dust from the sarcophagus, assuring him that she's fine. They get lovey-dovey and talk about going out that night until Lorne tells them to "get a balcony." Lorne starts singing "You Are My Sunshine" to Fred, who picks up the song. Lorne immediately realizes that something is wrong. Fred suddenly starts coughing up blood and collapses. Lorne catches her and she starts convulsing as Wesley yells for someone to get medical.
The gang and Knox are gathered around Fred in the medical wing when she regains consciousness. They try to assure her that she'll be okay, even though they don't know what's wrong with her. "Handsome man saves me," Fred says to Angel, bringing up an oft-repeated line from "Through the Looking Glass." Everyone leaves and Wesley tries to comfort Fred before heading off himself. Angel is surprised that he was the only person unaware of their new relationship. The guys meet up again in the lobby, where Knox says that Fred must have something mystical. Angel admits that some sort of parasite is slowly killing Fred. The gang wonder if the Senior Partners sent the sarcophagus; Gunn says he'll go to the White Room and see if he can talk to the conduit. Spike wonders if they can get in touch with Lindsey and get his help; Angel decides that it's worth a shot. He reminds the others that they're working to save Fred, and they all split up. In the medical wing, an uncomfortable Fred starts to turn a little gray. In his office, Wesley makes it clear to his staff that Fred is their priority by shooting a guy who isn't working on her case. Gunn goes to the White Room and tries to summon the panther, who doesn't appear. He gets socked in the face and turns to see that he's being hit by himself (or at least the conduit in the form of Gunn). The conduit tells him that he's failing and the Senior Partners are tired of his "insolence." Gunn wants to make a deal and give his life for Fred's. The conduit tells him that he already has Gunn's life.
Angel, Spike, and Lorne go to Lindsey's apartment, where they encounter Eve. She claims not to know anything about what's happening to Fred and says that she hasn't heard from Lindsey. Frustrated by her lack of info and concern for Fred, Lorne punches her and demands that she sing for him so he can make sure she's not involved in what's happening. Eve sings a little of "L.A. Song" and Lorne determines that she's not involved, though "her future's not too bright." As the guys leave, Eve asks if they're going to tell the Senior Partners where she is. She says that they can't help anyway; there's no info on the sarcophagus in the firm's records, but the only thing not in the firm's records is on the world's original demons. She says that Wesley's source books can bring forth any text and he needs to look through the oldest scrolls for information on the Deeper Well. In Wesley's office, he tells the group that the demon in question is called Illyria, "a great monarch and warrior of the demon age murdered by rivals and left adrift in the Deeper Well." The Deeper Well is "a burial ground, a resting place of all the remaining old ones." Fred's skin is "hardening like a shell," which makes Wesley think that she's being hollowed out so that Illyria can use her to return to the world. The Deeper Well is in the Cotswolds in England, and Angel prepares to go. Wesley explains that the Deeper Well will have a guardian, and it will contain everything on its sources so that they can be drawn back if they escape. As Angel and Spike head to England, Fred awakens with a start in the medical wing.
Wesley heads to the medical wing and is surprised that Fred isn't there. She's in the science lab, stumbling around and trying to work on her own case, since she doesn't want to have to be rescued. Noting that Wesley can summon any book he wants anywhere, she asks him to take her home. Angel and Spike fly to England, both nervous about the experience. Angel says that he can't lose Fred the way he lost Cordelia. Knox goes to Gunn and tells him that they should freeze Fred in the cryogenics lab until they figure out how to stop what's killing her. In her apartment, Fred starts asking for Feigenbaum, but cries when she can't remember who he is. Wesley reads A Little Princess to comfort her. Angel and Spike arrive in the Cotswolds and, at the possible entrance to the Deeper Well, get ambushed by a bunch of armored demons. They pull a stunt they once pulled in St. Petersburg, holding out a piece of wire and decapitating the first row of demons. They take their swords and use them against the rest of the demons. Knox tries to figure out how to freeze Fred in the science lab, but his tests don't work. He tells Gunn that he wants to save Fred, saying, "I don't just care about Fred, I practically worship it." Gunn catches his slip of the tongue. Spike and Angel finish off the demons and are met by Drogyn, the keeper of the Deeper Well, whom Angel knows from somewhere. He warns Spike not to ask him any questions, or he'll kill him. He knows that they're there about Illyria and invites them into the Deeper Well. As they head in, Angel explains to Spike that Drogyn doesn't like questions because he can't lie.
In the science lab, Gunn beats up on Knox, accusing him of causing what's happening to Fred. Knox denies that he caused anything, saying that he just played his part. "I chose Fred because I love her, because she's worthy," he says. "You think I'd have my god hatched out of some schmuck?" He tells Gunn that everything was set in motion millions of years ago and it can't be stopped. He says that Angel won't save Fred - "I don't mean that Angel's gonna fail to save her, I mean he's gonna let her die." Back at her apartment, Fred finds herself unable to stand the light and says that the cavemen win the battle. Drogyn leads Angel and Spike into the Deeper Well and gives them a little info - "the old ones were demons pure. They warred as we would breathe - endlessly. The greater ones were interred, for death was not always their end. Illyria was feared and beloved as few are. It was laid to death in the very depths of the well…until it disappeared a month ago." Drogyn thinks that Illyria's tomb was predestined to disappear, as part of the demon's escape plan. Besides, Drogyn is in charge of a bottomless pit full of coffins. He tells Angel and Spike that the pit goes all the way through Earth. He adds that Illyria must still have acolytes somewhere in the world. In the lab, Knox tells Gunn about these acolytes and adds that Gunn helped the sarcophagus get there - he unknowingly signed for it. Gunn says firmly that Angel will save Fred, but Knox tells him that "what he's fighting against is older than the concept of time." Gunn knocks him out.
Wesley tries to inject a delirious Fred with something, but her skin has hardened too much. In the Deeper Well, Drogyn tells Angel and Spike that the demon's essence has been freed. Spike gets fed up with Drogyn's no questions policy and starts asking a bunch of questions. Drogyn ignores him and explains, "The power to draw back Illyria lies in there. It requires a champion who has traveled from where it lies to where it belongs." If they bring the sarcophagus back to the Well, Illyria will leave Fred, but would then enter every person between L.A. and the Deeper Well and kill them. Angel decides that he might as well sacrifice the world to save Fred. In her apartment, Fred does some blathering and Wesley assures her that he won't leave her. Spike looks through the Deeper Well and says, "There's a hole in the world. Feels like we ought to have known." Fred asks Wesley if he would have loved her; he tells her that he's always loved her, even before he knew her. She asks him to tell her parents that she wasn't scared. As she weakens, she says, "Please, Wesley, why can't I stay?" She goes still and as Wesley hugs her, her eyes turn blue. Fred twitches and sends Wesley across the room, where he watches her turn blue. She stands up - now taken over by Illyria - and says, "This will do."