The following version of this book was used to create the guide: Kawakami, Mieko. All the Lovers in the Night. Europa Editions, 2022.

Mieko Kawakami's novel All the Lovers in the Night is written from the main character Fuyuko's first person point of view. The novel employs both the past and present tenses, and uses flashback in order to nuance the narrative structure. The following summary primarily uses the present tense.

After working for a publishing company since she graduated college, Fuyuko quits her job in order to become a full time proofreading freelancer. She is grateful for the job in that it allows her to escape her former coworkers, who not only ignored her but belittled and gossiped about her. However, working from home full time means that Fuyuko has even fewer opportunities for human interaction. She is a timid and passive individual, who is reluctant to take any action that might change her life. She prefers to operate within familiar spheres that present few challenges to her character and learned mode of operating.

Over time, Fuyuko's new boss Hijiri starts calling her regularly just to talk. The majority of these conversations are dominated by Hijiri's lengthy descriptions of her experiences, thoughts, feelings, and beliefs about people and the world. Fuyuko listens and absorbs everything that Hijiri says, impressed by her ability to know and speak her own mind.

After submitting a difficult manuscript assignment one day, Fuyuko feels an uncommon sense of exhilaration and possibility. She decides to use the feeling to get her to the Shinjuku neighborhood and enjoy the beautiful spring day. As soon as she arrives in Shinjuku, however, she feels overwhelmed and despairing. When she catches her reflection in a window, she realizes what a miserable person she is.

Fuyuko starts drinking regularly. She finds that alcohol gives her the ability to detach from herself and to ignore her usual worries and anxieties. The more she drinks, the more confident and unhindered she feels. Around the same time, she decides to visit the Shinjuku culture center and register for a few classes. While there, she runs into a man named Mitsutsuka, who notices Fuyuko is not feeling well. She has been drinking since the morning, and has thrown up after guzzling a can of coffee.

Although their first encounter is awkward, Fuyuko and Mitsutsuka begin meeting up at a cafe in Fuyuko's neighborhood every Thursday. Whenever they are not together, Fuyuko obsessively replays their conversations and interactions in her mind. She does not understand why she is thinking about Mitsutsuka so much when she knows so little about him. The more they see each other, the more attached she becomes. Despite her investment, Fuyuko feels powerless to identify, explain, and thus vocalize her feelings.

One day, Fuyuko reunites with one of her former editors Kyoko after attending their old boss's funeral. Kyoko spends their visit badmouthing Hijiri, insisting that she is using Fuyuko because Fuyuko is weak and passive. Not long later, Fuyuko reconnects with her old high school friend, Noriko. Noriko spends the visit lamenting the negative aspects of her life, including her marriage and her affair. Afterwards, Fuyuko feels overwhelmed by loneliness and despair.

Fuyuko falls into a deep depression. She lessens her workload, stops leaving the apartment, and barely gets out of bed. The more time she spends in this manner, the worse she feels. Then one day she decides that she is upset because she has not told Mitsutsuka that she likes him. She calls him and they discuss their feelings, making plans to meet up for their birthday.

Fuyuko takes Mitsutsuka out to an expensive restaurant for dinner. Afterwards, they stand under a tree talking and Fuyuko tells him she is in love with him, bursting into tears. Mitsutsuka holds her, but says nothing. When she returns home afterwards, she finds Hijiri waiting irate on her doorstep. Hijiri berates and ridicules Fuyuko, triggering Fuyuko's old traumas and making her cry. Hijiri apologizes and tells Fuyuko she needs her friendship.

Over the following two years, Fuyuko and Hijiri become close. Fuyuko supports Hijiri when she decides to go through with her pregnancy and raise her child alone. Two years prior, Mitsutsuka stopped talking to Fuyuko. He wrote her a letter explaining that he had lied to her about who he truly was. It took her a while to recover, but Fuyuko eventually found peace.