The story is set in 1984 Japan, and it revolves around Aomame and Tengo, two individuals whose fate became intertwined from when they were ten-year-olds and Aomame tightly squeezed Tengo’s hand and made an unknown promise to the moon. Now, they are both around thirty, Aomame being a sports instructor while secretly working as an assassin for a rich dowager with the intention to remove those who are a threat to women, and Tengo being a part-time math teacher and part-time writer.
One day, Tengo finds himself pushed into a somewhat illegal job of rewriting a novel called Air Chrysalis, written by an ambiguous teenager under a pen name Fuka-Eri. Parallel to this, Aomame finds herself stuck in traffic, and, encouraged by the taxi driver, takes a shortcut to the railway station by going down a ladder that leads into an underground secret railway passage. Aomame is on a mission to kill a man holding an important position. Aomame works for a dowager who is in charge of a safe house for victims of domestic violence and who takes the matters of punishing the abusers into her hands.
Throughout the novel, Aomame discovers that the world isn’t the same as it was before she ascended the ladder. There are two moons on the sky, and she seems to have missed some important changes that took place. Tengo, on the other hand gets closely involved with Fuka-Eri, while contemplating his past and relationship with his father. It gets slowly revealed that the Air Chrysalis is a story that depicts reality, and the Little People, Two Moons and maza and dohta (two pieces of a whole person) are real.
When the leader of the religious group that follows the principles from Air Chrysalis gets killed by Aomame, the witch hunt for her ensues, as the distance between her and Tengo gets smaller. At the end, the two of them reunite after two decades of keeping each other in their hearts and escape the world of 1Q84, and return to 1984 with only one moon in the sky.
The main theme that the novel explores is the theme of alternate universe with religion and fantasy sprinkled in. It also explores several, more controversial, topics.
