The book begins with the Shadow Leech attack on Takanuva. He manages to kill the leech, but passes out, and is brought to the Archives, where he meets Helryx, who is the first Toa and the leader of the Order of Mata Nui. Also there is Toa Krakua, and he and Helryx use a "Kraatana" to show Takanuva a vision of the past. He sees the creation, training, and early operations of the Toa Mata. He sees the Toa Mata enter an enormous sphere in Karda Nui called the Codrex, upon which a massive energy storm appears in Karda Nui, reducing the abandoned Matoran settlement to ashes. The Toa then enter their canisters, which protect them from the storm and put them to sleep until they are needed.
Note that this vision was described in a series of flashbacks throughout the book, told intermittently with Tahu, Gali, and Onua's battles in the Swamp of Secrets, which happened as follows:
Tahu, Onua, and Gali enter the swamp, and decide to split up to search for the Mask of Life. As Onua searches, he discovers (at the expense of an unfortunate Nui Kopen) that the waters of the swamp are mutagenic. He is then attacked by Makuta Bitil, who uses his Nynrah Ghostblaster to seize control of Onua's mechanical components, in effect taking over his body, and also reveals the power of his Mask of Duplication. Onua eventually escapes when the effect of the Nynrah blaster wears off.
Meanwhile, Gali finds one of the keystones and retrieves it. She is then attacked by Makuta Gorast, who starts to drain Gali's life energy to feed on. Onua then arrives and saves Gali, and the two fly away.
In the meantime, Tahu discovers an enormous sphere. Due to his memory loss, he does not recognize it, but it is the Codrex. He encounters a force field protecting the sphere which can only be permeated by placing the keystones in the correct place. The energy field throws him backwards and knocks him unconscious, and Makuta Krika arrives and prepares to feed on Tahu's energy. Tahu awakens and confronts Krika. He is then joined by the other two Toa Nuva, who are closely pursued by the other two Makuta. The three Toa and three Makuta prepare to do battle, but are distracted by the sight of Makuta Chirox falling from the sky, having been hit hard in an arial battle. As Krika, Gorast, and Bitil move off to save Chirox (that was nice of them), the Toa Nuva escape and are brought by an Av-Matoran to a small camp where several more Matoran are located. It is there that the Toa learn a shocking secret: when the Av-Matoran reach the end of their lifespan, they transform into Bohrok. The new Bohrok then disappear, teleported away to join the swarms in the nests beneath the island of Mata Nui. Before transforming, the Matoran that brought them there presents them with another keystone, and then fulfills his grim destiny by becoming another machine of destruction.
The Toa Nuva then head to Krika's base camp and attack, stealing the last keystone and making their escape. The Makuta then go to the Codrex and take up positions of ambush, knowing that the Toa must come there to complete their mission. They do come, and mount their attack, but then the Phantoka arrive. The six Toa Nuva join together once more, along with Tanma, Solek, and Photok, and Antroz, Chirox, Vamprah, and their Shadow Matoran back up Krika, Bitil, and Gorast. The status of Toa Ignika, Icarax, and Mutran is not known. With all six keystones is their possession, the Toa Nuva and Matoran of Light prepare to face the forces of darkness in the final battle.
Back in Metru Nui, as Takanuva's vision ends, Helryx introduces him to Brutaka, who has captured the Dark Hunter Dweller. They then inform Takanuva of his new mission: they will send him to the Universe Core, where he must find the Toa Nuva and deliver a warning to them: when they accomplish their mission, and awaken the Great Spirit Mata Nui, the energy storm will hit Karda Nui once more, and everything there will be incinerated. The only way for the Toa Nuva to survive and continue the fight lies within the Codrex, and only with the knowledge Takanuva carries can they use it.
Bruaka then activates his mask, sending Takanuva off on his great journey, and as the members of the Order of Mata Nui head for the surface to make preparations for their attack on the Brotherhood of Makuta, Krakua wonders aloud if Takanuva will make it, and if it would have been wiser to inform him of what they know about his destiny.

есть мнение, что сестры Бараг из-за их размеров могли быть неизвестными никому Тоа Света

Тогда что с Бороками Ва и Кал?

Калы - обычные мутанты, а Ва могут и не быть дохлыми Маторанами - они же не зависят от Кран.

Я текст не читал ибо не понимаю, объясните плиз как это? Матораны и бороки же совсем не похожи. Разве может благородный, живой, с органическими тканями, ав-маторан превратится в механического борока которыми какие-то краны управляют??? Хотя крааты же как-то превращались в доспехи....Ничего не понимаю. (с) А нельзя ли этот текст как-нибуть перевести?...

Все в спойлерах нах!

Текст я намеренно не намерен переводить Там такая куча спойлеров, и для вас это будет замечательный стимул учить английский. Вот такой я жестокий! Или ждите книгу. Я, конечно, пытаюсь сейчас надыбать сканы, но америкосы же нутууупыыыеее...
Я подозреваю, что это просто особенный механизм трансформации, связанный, как обычно, с судьбой. Судя по краткому содержанию, полудохлый Маторан Света превратился в Борока прямо на глазах у Мистика.