In the wake of Gregor’s injury, which limits his mobility, the family takes pity on him and leaves the bedroom door open at night so Gregor can watch them. The father dozes in his chair while the mother sews lingerie for a boutique and Grete studies French and shorthand in hopes of moving up from her job as a sales clerk. The father stops taking off his bank attendant uniform when he comes home, and the uniform becomes increasingly filthy. Grete and the mother encourage the father to go to bed early, but he stays up late every night, muttering about how sad his life has become.

Gregor learns that the family has been selling off jewelry to bring in money, and they replace their regular maid with an elderly cleaning lady. He also realizes that they feel trapped by his presence. Gregor stops sleeping and eating as he frets about the family and the past, alternating between guilt over not helping them and outrage that they have neglected him. Grete hardly takes care of him at all anymore. Despite this apparent indifference to Gregor, she becomes extremely upset when the mother cleans Gregor’s room and insists that Gregor is hers to look after.

The new cleaning lady, meanwhile, regularly talks to Gregor. She openly stares at him, and even tries to sneak into the room to catch him off-guard. One day, Gregor, tired of being peered at, attacks her, but the cleaning lady threatens him with a chair, so he desists.

The family takes three boarders into the apartment. These men cannot stand mess and disorder, so the family moves much of the furniture and the cleaning lady’s supplies into Gregor’s room. Gregor enjoys crawling through the clutter, though doing so leaves him exhausted.

One night, the cleaning lady accidentally leaves the door open while the boarders are home. The boarders eat in the dining room while the family eats in the kitchen, and Gregor notices the boarders being very picky about the food that his mother and sister have cooked. Hearing Grete playing the violin, the boarders invite the family into the parlor. The boarders initially stand very close to Grete as she plays, but they soon lose interest. Gregor is entranced by the violin and slowly creeps out into the parlor. He longs to take his sister back to his room and tell her about his plan to send her to music school.

One of the boarders spots Gregor and cries out. The father rushes the boarders out of the parlor as they declare they will move out and not pay rent. Grete tells her parents that they have to stop believing that the bug is Gregor and says they must find a way to get rid of it. The father wishes they could explain to Gregor why they need him to leave, but Grete says that if he could understand them, he would have left long ago to spare them any more pain. Gregor, feeling terrible, scuttles back to his room. He remains motionless through the night, thinking to himself all the while that he must go away to relieve them of their suffering. As dawn breaks, he dies.