This synopsis will contain spoilers!
Takeo and Kaede are married and living in Terayama. They travel with the Otori soldiers who have joined Takeo to Maruyama where Kaede will take over her lands. Takeo must fight a giant man and a group of bandits along the way. When they arrive at the borders, they see another army has already arrived. With the help of a local boy (Hiroshi), they trap the invading army and defeat them. Kaede is welcomed with some hesitation as the rightful ruler of the land.
Takeo journeys with Makoto to an island where there are pirates who he must convince to help in the invasion of Hagi. He is successful, but is delayed in returning to Maruyama because of a typhoon. Meanwhile, Kaede decides to visit her childhood home to see her sisters and gather news. She hides the records of the Tribe nearby, and when she arrives finds her sister gone. She goes to Lord Fujiwara to discover what happened to them, where she is kidnapped and forced to marry him.
Hiroshi escapes from Fujiwara and returns to Maruyama in time to tell Takeo what happened upon his return. Takeo takes half his army and marches to Fujiwara to rescue Kaede. Just before he arrives he discovers Arai, the warlord, has his army there and Takeo must flee. They almost escape to the coast and the pirates when a typhoon blocks them in. He surrenders himself to Arai who forms an alliance with him to defeat the Hagi.
Meanwhile in the hidden Tribe village of Muto, Kenji (Takeo's teacher) discovers his daughter Yuki was murdered after giving birth to Takeo's son so the Kikuta clan could raise the boy to hate his father. Kenji and Shizuka decide to help Takeo in revenge for the murder of Yuki. They arrive in Maruyama in time to discover the alliance. Shizuka heads to Fujiwara in an attempt to discover news of Kaede.
Takeo goes to the pirates and invades Hagi in secret. He kills the men who betrayed Shigeru and they take the city. Arai betrays them, but his pirate friend shoots Arai with a gun and kills him. Takeo takes over the Three Countries. Meanwhile, Kaede is about to witness the execution of Shizuka (after being caught in bed with Fujiwara's doctor), but an earthquake sets the house of fire killing Fujiwara. Kaede escapes with Shizuka and the doctor, but all her hair is burned off.
Takeo, Kenji and Taku (Shizuka's son who has a lot of Tribe abilities) kill the Kikuta master who comes to kill Takeo. Takeo goes to the secret place where the Tribe records were kept where he meets Kaede again. He says whether or not his son kills him as the prophecy said is for another Tale of the Otori.
There's no other way to say this than Brilliance of the Moon is a disappointing book. I've thought a lot about why this is - why did I enjoy ...- Feb. 18, 2012
Lian Hearn the Last Line of in Brilliance of the Moon