A short time later, Marian comes to consult with Walter. Laura has received a letter delivered by an elderly woman. The letter is anonymous and describes a dream in which Laura is marrying a man who is not named, but who is described in precise physical detail, all of which matches up with Sir Percival. The dream turns into nightmarish vision of the threat the man poses to Laura, and the letter ends with the writer cautioning Laura to investigate her fiancé's past before marrying. It also describes the letter writer as having been a close friend of her mother. Marian wants to know if Walter thinks they should start trying to find out who may have written the letter, or wait for the arrival of the family lawyer, Mr. Gilmore, and ask for his help.
Walter can't help wondering if uncovering information about Sir Percival might break off Laura's engagement, so he suggests that he and Marian try to find out more about the origins of the letter. They ask around the village but can't get any information. They finally arrive at the village school, where the teacher is scolding a boy named Jacob Postlewaite for claiming that he saw a ghost. Under further questioning, he claims it was the ghost of Mrs. Fairlie. The teacher explains that Jacob claims he saw a woman in white at Mrs. Fairlie's grave, and that it therefore must have been her ghost. Walter begins to suspect that who Jacob actually saw was Anne Catherick, and shares this suspicion with Marian. He then decides to watch at Mrs. Fairlie's grave overnight to see if anyone comes back.
At twilight, Walter sees two women enter the graveyard, one elderly and one young. The elderly one leaves her companion, who begins tending to Mrs. Fairlie's grave. Walter approaches her, confirming that she is the same woman in white he has met before. She is startled but reassured when he reminds her that he was kind and helpful to her before. He explains that he has been staying at Limmeridge house, and also tells her that he knows she escaped from the asylum. She becomes agitated upon hearing this, but he reassures her that he is happy to have helped. Anne explains which asylum she escaped from, and how once she got to London, she took refuge with her friend Mrs. Clements. Two days prior, the two women traveled to a nearby farm called Todd's Corner to stay with some of Mrs. Clement's relations.
Walter uses this opportunity to discreetly probe into whether Anne was seduced by Sir Percival, since he suspects that might have been her motive for writing the letter to Laura denouncing his character. She completely rejects this possibility, leaving him confused. He openly accuses her of having written the letter, which she tries briefly to deny. Then Walter suggests that if she will agree to meet with Laura, she can disclose whatever warnings she needs to. By now, however, Anne is becoming very agitated, especially when Walter refers to whomever put her in the asylum. When he mentions Sir Percival's name, she screams in horror and he realizes that it must have been Sir Percival who put her in the asylum. Anne's scream brings Mrs. Clements hurrying back, and the two women hurriedly depart.
Walter returns home and tells Marian what has happened. He initially proposes that Laura and Anne meet, but Marian rejects this idea. She does agree to go with Walter to the farm the following day to speak with Anne herself, and vows to get to the bottom of why Sir Percival placed Anne in an asylum and presumably paid for it. The next morning, Walter gives notice to Mr. Fairlie that he is leaving his job, and then he and Marian go to the farm. They are surprised to find that Anne and Mrs. Clements left first thing in the morning, with no explanation and in a great hurry. After questioning Mrs. Todd and her daughters, it comes to light that Anne was informed of the expected arrival of Sir Percival at Limmeridge House, and Walter is convinced that this why Anne and her mother fled.
Back at the house they encounter Mr. Gilmore, the lawyer. The plan is that he will help to determine if Sir Percival is trustworthy and whether or not Laura should marry him. Mr. Gilmore sends a copy of the letter to sir Percival's lawyer, and has also sent servants out in hopes of tracking down Anne and her companion. He assumes that Anne's motive for denouncing Percival was unrequited love, and does not seem overly alarmed about the case, though he promises to investigate it faithfully. The servant reports back that he was unable to trace the two women, so there is nothing else to be done. In the meantime, Walter is preoccupied with his departure. Before he leaves, he says a heart-rending good-bye to Laura, who gives him a drawing she has made.
This section sheds light on Walter's feelings for Laura, and his motivations for pursuing the source of the letter she has received. Although he has tried to be respectful of Laura's engagement, he would be very happy to see it ended, and he is therefore very motivated to find out if there is something sinister or dangerous about Sir Percival. He is partially concerned about protecting Laura, but also hopeful that this might help his own chances of being with her. Even Marian, who is very protective of Laura, is not sure at first how seriously to take the letter, and whether it is worth investigating. In contrast to Mrs. Fairlie's letter, which seemed to create truth by identifying the woman in white, this letter is viewed by everyone with some skepticism and no one is sure how seriously to take it.
Part of why the letter is viewed with suspicion is that many characters assume it was sent by a jealous or spurned lover who is now angry that Sir Percival is going to marry someone else. Mr. Gilmore certainly sees it that way, suggesting that both his logical and pragmatic legal training, and his experience as a middle-aged man who is longer inclined to romantic ideas the way that Walter is, make him unconcerned about any real danger. While Walter is more worried that there is real danger, he too assumed in his conversation with Anne that she and Percival were having a sexual relationship, and that that is how he betrayed and damaged her. Walter is very surprised when this turns out to not have been the case.
These assumptions suggest how stereotypes about women tend to focus on them being at least partially at fault; whether or not they are sympathetic, Mr. Gilmore and Walter at first assume that Anne's motivations derive from her resentment at not being chosen by a man. Ironically, their failure to believe her story and the suspicion with which they view her account will end up placing Laura in danger. The way in which the letter is presented also undermines its credibility. Rather than describing factual events, the author writes about a dream vision. Especially for characters who look at events in a very practical and logical way, it is easy to dismiss this as simply paranoia or even madness.
Walter's encounter with Anne at the grave of Mrs. Fairlie is a classically Gothic scene that recreates the drama and tension of their first encounter. He is able to gain some new information, but is still left with many questions. The dramatic tension of the narrative builds, in that it seems increasingly likely either that Anne is insane, delusional, and lying, or that there is something truly dark and sinister in Sir Percival's past.