When Alexei enters Lise’s room, he finds her sitting in her former wheelchair. She doesn’t move but looks at him sharply. She tells Alexei that she just overheard his entire conversation with her mother. Alexei notes that there’s something “wicked and guileless” about Lise now. She tells Alexei that she loves him very much, but she doesn’t respect him. Alexei asks why Lise sent for him. She says that she wants someone to marry her and torment her. Then, she expects that person to deceive her and leave her; she doesn’t want to be happy. She wants “disorder.” She would even like to set fire to her house.
Lise is sitting in her former wheelchair, though she now has the ability to walk, because she doesn’t seem to believe that she’ll be accepted if she isn’t infirm. At the same time, she seems to resent this and registers anger. She no longer respects Alexei because of his indomitable goodness—Lise is now choosing pain and disorder, as though she wants everyone else to suffer as much as she believes she has to.
Alexei says that her rich life is the cause of her discontent, but Lise doesn’t think it’s better to be poor. Lise says, in fact, that she’d love to remain rich while everyone else is poor. She’ll “eat candy and drink cream” and share none of it. She waves a hand in indifference. If she’s ever poor, she says, she’ll kill someone. Then again, maybe she’ll do that anyway.
Lise’s anger could be partly the result of her mother continually frustrating her burgeoning sexuality with her spying and overprotecting. She becomes resentful and finds pleasure in what she’s permitted: suffering. She wants to feel it and inflict it. Lise has changed drastically and is having a crisis common to many of Dostoevsky’s characters, becoming transgressive and nihilistic in the face of a meaningless world.
Alexei says that Lise takes “evil for good,” which he chalks up to “a momentary crisis,” due to her illness. Lise says that she wants to do evil, and her illness has nothing to do with it. Alexei asks if Lise isn’t ashamed. She replies that she wants to ruin herself. She mentions a boy who lay down under the rails while a train went over him (Kolya) and calls him “lucky.” She also mentions that people actually love that Dmitri killed his father, though they say that it’s terrible. Lise says that she’s “the first to love it.”
Lise feels incapacitated and frustrated, and lashes out in response. Like Kolya, she suffers from an overprotective mother. Unlike him, her gender and her paralysis prevent her from emancipating herself through forms of rebellion, though she attempts this by offering herself to Ivan. Alexei chalks up her frustration to an absence of faith.
Lise tells Alexei to go to his brother. She pushes him out the door and gives him a letter addressed to Ivan. She demands that he give it to his brother. This, Lise says, is the reason she sent for Alexei. She then slams the door. Once he’s gone, she unlocks and opens the door, puts her finger into the chink, and slams it again, crushing her finger “with all her might.” She returns to her chair, looks at her blackened finger and the blood oozing from the fingernail, and whispers to herself about how mean she is.
It's never made clear what Lise says to Ivan in the letter, but he never replies to her. He only mentions to Alexei that Lise once offered herself to him, but it seems more likely that that occurred during Ivan’s unchaperoned visit. Lise’s self-mutilation is the result of believing that no one will pay attention to her unless she is in pain—it is also a reversal of how concerned she was about Alexei’s hurt finger not so long ago. This is a brutal ending for Lise (who doesn’t appear again in the book), as she turns to inflicting pain on herself and others in an attempt to make sense of the world.