An eighteen year old Alexandra Trese is spending time in the family library the night before she goes through the Great Balete Tree Trials. As she goes through the library, she notices a book she has never seen before. When she starts to read it, a shadow like entity appears and attacks her. The Kambal barge in and help her, but Anton Trese appears with Alexander, who commands the entity to stop.
Alexander explains that the entity was a guardian who defended the book from anyone other than him and Anton. After Alexandra confesses to seeing their name from her brief glance at the contents, Anton and Alexander agree to explain everything to her. They reveal that the book contains a collection of prophecies from seven psychics around the country, one of which was her own mother Miranda Trese.
Among the prophecies were the fates of five children who came to be Anton and Miranda's children. They also explain that she had an older twin sister who died soon after her birth. She was immediately taken to the Metalero who, with the assistance of the Babaylan of Makiling forged her into a kris that was named the Sinag. On her baptism, the kapre, diwata, duwende, aswang and tikbalang all gave Alexandra gifts as well as the Cloak of Takipsilim. This is in acknowledgement of her fulfillment of one of the prophecies, where she is fated to choose to either let the Underworld conquer Terra Mundo, leading a seige on Skyworld; or to seal the Underworld's gates, banishing its creatures from ever returning.
She asks them about the prophecies regarding her tests the next day, which she saw from her brief glance at the book. They tell her that there would be four rebelling tribes of aswang that will invade the Great Balete Tree, not trusting that Alexandra would choose the right path. Anton also tells her that one of the prophecies was that "the blood of Trese will soak the roots of the Great Tree." Knowing this, Alexandra refuses to take the test, but Anton points out that the aswang would come and kill her regardless.
The next morning, she proceeds with the Great Balete Tree Trials protected by her family and the Kambal. Some of the family's allies also showed up to protect her, including duwende and their lamang lupa, tikbalang, kapre, Hank Sparrow and even Captain German. To help her, they give her the Sinag, the Cloak of Takipsilim, and all the other gifts given to her on her baptism.
After a few words with her father, she goes into the Great Balete Tree, promising to make it as quick as possible. She journeys into the depths of the tree, eventually meeting a tikbalang as her first test. While she undertakes the Trials, an onslaught of aswang start attacking.
Eventually, she emerges from the tree and is greeted by the Kambal, Enrique Trese and Alexander, who is now confined to a wheelchair. They explain that three years have passed since she went into the tree, and that Anton gave his live to protect her, casting a spell over the Great Balete Tree. Alexandra gets angry at the Kambal, as she expected them to protect her father, but Alexander clarifies that Anton ordered them to protect him instead. They also tell her that Carlos, Matthias and Jimmy Trese went into the Underworld to continue the battle.
Alexandra leaves, bringing the Kambal with her, and chooses to start undertaking her responsibility as the Babaylan-Mandirigma,
- This is the first case to mention Alexandra's siblings.