After they finish reviewing the letters, Roland shares his guess that Christabel may have accompanied Ash on a trip to Yorkshire in June 1859. Ash was always assumed to have gone alone in order to focus on studying natural history, and there are letters he sent to his wife from this trip. However, the content of the letters suggests that Christabel and Randolph reached some sort of decisive agreement around this time.
Unable to do anything else, they each return to their work, and Roland sends off several job applications. A few months later, in April, Maud and Roland go to visit the house in London where Christabel and Blanche had lived together. Afterwards, they discuss their theory. A gap in information about Christabel's whereabouts fits within the timeline; there is no firm record of her until Blanche's suicide in June 1860. They decide that Ellen Ash's journal might contain helpful information, and Maud decides to reach out to Beatrice. When she phones Roland one evening to confirm that she will be visiting Beatrice the next day, Val is cold and rude to her on the phone. She is also curt with Roland about the phone call later, irritating him.
Maud and Beatrice discuss Ellen's journal, with Beatrice confiding the challenges and uncertainties she faces. Ellen's journal from June 1859 describes the experience of being alone in her husband's absence, and her inner conflict about what to do with a maidservant experiencing an illegitimate pregnancy. She also notes receiving a jet brooch as a gift from Randolph. There is a brief mention of receiving a letter from a woman insisting on meeting Ellen, which is not an unusual request due to her husband's fame. She seems to say that she did eventually meet with the woman, but notes very little of what they discussed, focusing instead on a long period of ill health. Intrigued by this mention, Maud asks to see Ellen's letters, and finds the one referred to in the journal. It is a frantic note, signed Blanche Glover. Another fragment in the same writing refers to Ellen having kept some sort of evidence that Blanche provided her with.
Before Maud can figure out what to do, Beatrice observes that she seems to have found information she was seeking. Maud admits she has, stating only that she has an idea of what Blanche might have been telling Ellen about. She asks to make copies of the letters from Blanche, the relevant section of the journal, and for Beatrice to refrain from telling anyone about what is going on. Beatrice agrees; as Maud is leaving the library, she runs into Fergus, who tries to question her about what is going on, and what she is doing with Roland. When she refuses, he threatens to find out for himself.
A few days later, Roland and Maud meet and she shows him what she has found. He suggests that Blanche probably showed Ellen the stolen correspondence, and that it seems plausible she did so because she was angry that Christabel had gone to Yorkshire. However, they still have no proof that she accompanied Randolph on the trip. They come up with the idea of exploring Yorkshire to see what clues from the writings of both poets might seem to fit with the theory of them having been together there; in order to provide funds and a cover story, Roland plans to apply for a grant to do research on some Ash papers at the York Minster Library.
A short time later, the two of them are staying together in a small inn and planning to explore the places that Ash seems to have visited. Roland begins reading Leonora's scholarship on Christabel, but finds her focus on sexualized interpretation distasteful. Meanwhile, Maud is reading Cropper's biography of Ash. They visit the town of Whitby; both Ellen's journal and Ash's letters to her mention him having purchased a jet brooch there as a gift for her. They stop at a jet shop, where Maud is selecting a gift for Leonora, when the shopkeeper comment on Maud's own brooch as a notable piece of Victorian-era craftsmanship. Maud comments that she found it amidst family items as a young child, and the two of them are struck by the idea that it might have once belonged to Christabel or even purchased on the very trip they are researching. As Maud and Roland explore and read further, they become increasingly convinced that Christabel must have visited Yorkshire. They also get to know each other better, discussing their perspectives on life and art. One day on the beach, Maud playfully reveals her hair to Roland, something she has never done before.
The narrative switches to the past, describing Christabel and Randolph travelling by train to Yorkshire together, agreeing that she will pose as his wife during their trip. Their first day there, they explore the seacoast and that night, they make love for the first time. They spend the rest of their time away idyllically happy, while also knowing that they are only enjoying a fleeting period of joy. The narrative breaks to switch to an excerpt from Christabel's poem about Melusina.
The novel's momentum builds on the fact that each discovery raises new questions and deepens the mystery. The initial letters Roland found suggested only attraction, but did not confirm a relationship, while the letters found at Seal Court confirm a correspondence and emotional bond between the two poets. They do not, however, answer a key question Roland and Maud find themselves obsessed with finding out: did Ash and Christabel ever consummate their relationship? To do so would not have been easy, considering that Ash was married, and a highly visible public figure; more generally, strict social protocols did not facilitate men and women finding opportunities to speak in private, let alone pursue a sexual relationship. However, both pragmatic and literary evidence seems to support the possibility that Christabel and Ash may have travelled together, and if evidence that the two poets wrote to one another would be a significant discovery in and of itself, Roland and Maud now realize they are truly on the brink of discovering something that would completely change how both writers are understood.
The increasing impact of their potential discovery means that the stakes are increasingly high: even in the world of literary scholarship, sex sells. While Fergus and Beatrice are almost total opposites in their scholarly demeanors, both of them are increasingly aware that Roland and Maud seem to be up to something. The fact that Roland and Maud are an attractive couple who suddenly seem to be spending a lot of time together both increases scrutiny of their quest, but also gives them a potentially convenient disguise. Fergus would be less inclined to pry if he was not jealous and suspicious that Roland and Maud might be having an affair, but this possibility also acts as a potential red herring to make it unclear precisely what it is the two of them are trying to hide.
Unlike Fergus and Beatrice, Val does not consider the possibility Maud be a collaborator, and clearly sees her as a rival. This section neatly weaves together the experiences of three women faced by romantic rivals: Val in the present day, and Blanche and Ellen in the Victorian era. Confronted with the idea that their partners might be facing temptation, both Val and Blanche react with anger and attempts to put a stop to the interactions they perceive as threatening. After Blanche's initial interference with the letters fails, she goes directly to Ellen, assuming that Ash's wife will have a comparable motivation to put a stop to the relationship. Ellen's reaction is obscured, but the storyline about her pregnant maidservant creates a parallel situation in which she struggles between compassion and a rigid adherence to social conventions that would condemn any woman for pursuing sexuality outside of marriage.
While these abandoned partners brood, the move to a new place creates an atmosphere of freedom for both the modern and Victorian couples in this section. Unlike the more traditional research methods they have used up to this point, Roland and Maud are now reliant on an experiential, intuitive, and even emotion-driven search for evidence. While they still demonstrate their skill as close readers by noting echoes in the writings of the two poets and references that would support arguments for Christabel having visited Yorkshire, they lack the hard evidence the letters they have provided up to this point. Instead, they have to rely on their gut intuition and the affirmation they receive from each other. This experience of confirming their hypothesis with each other draws them even closer together, as does the experience of imagining what the two poets must have felt while they moved through the same places in an emotionally charged period.
In order to complement this speculation, and offer the reader the certainty that Roland and Maud lack, Byatt includes a chapter set in the Victorian era and told directly from the point of view of Ash and Christabel. Up until this point, letters, diaries, and excerpts of literature have provided the voices of characters from the past. Now, the reader get to be fully immersed in the world of the poets using the more familiar form of historical fiction. This shift is necessary to convey the physical and emotional intimacy experienced during this time abroad: most likely neither character would have written about what they experienced. In a novel where written records function as powerful records of the past, it is notable that Byatt chooses to narrate the brief window in which Ash and Christabel actually lived as lovers as something that goes unrecorded, and lost to time. This choice creates a sense of privileging the privacy of the two poets: Roland and Maud will uncover some things, but they won't have access to all the intimate details, because there are always limitations on what history can ever capture and record.