A couple in their thirties receives a notice that their power will be shut off for an hour each evening for five nights. Shukumar is a student who works at home on a dissertation. Shoba, his wife, works in an office as a copyeditor of textbooks. Shoba comes home and reads the notice from the electric company aloud. She reminds Shukumar about his upcoming dentist appointment, and Shukumar realizes he did not brush his teeth that morning. Shukumar remembers a time six months ago when Shoba was pregnant. She was due any day but insisted that Shukumar go to an academic conference in Baltimore anyway. She said she would call him if necessary and have a friend take her to the hospital in case of emergency. His cab was a station wagon that day, and as he rode away, Shukumar thought about how he and Shoba might one day need a station wagon to bring their kids to music lessons and dentist appointments. At the conference, Shukumar got a message from the hospital explaining that the baby was born dead and that Shoba was recovering. Shukumar rushed home.

The power outages occur six months after the tragedy. By this point, the couple hardly speaks to one another. Shukumar struggles to write his dissertation, and Shoba does not maintain the house like before. Shukumar thought things would improve, but they haven’t. After reading the notice, Shoba goes upstairs to shower. Shukumar finds a new toothbrush in the downstairs bathroom and brushes his teeth. He thinks about how he rarely goes out of the house these days and how Shoba is rarely home. He and Shoba have become experts at avoiding each other. The extra toothbrush reminds Shukumar of how Shoba used to buy huge amounts of food at the market and prepare meals and dishes with ease. She used to cook for friends and make preserves. Now, Shukumar looks through her cookbooks each afternoon and chooses something to make for dinner because she doesn’t cook anymore. They usually eat separately. Shoba takes her plate to the living room and Shukumar takes his to the study, which would have been the baby’s room. Shukumar removed the baby wallpaper, rocking chair, and crib after the baby died so Shoba wouldn’t see it.

On this night they dine together in darkness so Shukumar finishes preparing dinner and gets birthday candles from a drawer. He remembers the candles were from a surprise birthday party Shoba threw for him. There were more than a hundred people in the house. Since the baby died, only Shoba’s mother has visited. Shukumar bitterly reflects on how Shoba’s mother indirectly blamed him for being out of town when the Shoba went into labor. They eat by candlelight. Shoba seems surprised at the dinner Shukumar has prepared. As they eat, Shoba suggests that they tell each other something in the darkness. When there were power outages at her grandmother’s house in India, they always had to say something in the darkness, to tell a joke or recite a poem. She wants them each to divulge a secret in the dark. Shoba tells Shukumar that after they first met, she checked his address book to see if she was in it yet. Shukumar tells her that he forgot to tip the waiter when they first went out to dinner, so he returned the next day to leave the tip. Shoba asks him why he forgot, and Shukumar says that at the end of the meal he thought he might marry her one day, and the thought distracted him.

The next night they eat leftovers and Shukumar is surprised when Shoba does the dishes. Seeing their reflection in the kitchen window, Shukumar wonders when they last took a picture together. He remembers that his camera still contains undeveloped photos of Shoba while she was pregnant. He looks forward to telling more secrets. They sit out on the porch during the power outage and see some neighbors headed to the bookshop, which still has power. When the time comes for their nightly confessions, Shoba tells him that she stayed out late with a friend once when Shukumar’s mother was visiting. Shukumar had wanted her to be at home because his mother was still grieving for his father, and Shoba always knew the right thing to say. Shukumar confesses to cheating on a test a few months after his father died, fifteen years ago. He feels tremendous relief for divulging this little secret.

On the third night, Shukumar confesses to returning a sweater Shoba gifted him. Shoba confesses that she let him talk to the head of his department at a party once with a smudge of pâté on his face. That night, Shukumar and Shoba kiss on the couch. On the fourth night, Shukumar tells her that during her pregnancy, he came across a picture of a woman he was sexually attracted to in a magazine. He tore it out and kept it. Shoba tells him that she never liked a poem he wrote that was published in a literary magazine. The couple feels closer than they have in months. The confessions make it easier to talk to each other. On the fourth night of confessions, Shukumar and Shoba make love.

On the fifth day, a notice comes in the mail that the workmen have finished early and there won’t be a power outage that evening. Shukumar feels disappointed as he had been looking forward to their nightly ritual. They turn off the lights that night and eat by candlelight. After dinner, Shoba turns the lights on because she has something to tell Shukumar. She has been looking at apartments and she found one she likes. She tells him she is moving out. Shukumar is stunned. He can’t think of what to say, but then he tells another secret. Shoba had never wanted to know the sex of their baby and held the mystery of it close. Shukumar had held the body of the child, however, so he knew the sex. He tells her that the baby was a boy. Shukumar takes the dishes to the kitchen. To Shukumar's surprise, Shoba follows him and turns off the lights. Together, they cry in the darkness.