Describe the events surrounding the curse of Lucas.

The Trementina sisters, known as the brujas (witches), put a curse on Lucas because he discovered their secret ceremony, where they created "fire balls" during a "Black Mass" in honor of the devil. The doctor in town and the priest in the village were unable to cure him of this curse and Lucas lay near death. Pedro came to Antonio's house to talk to mother to see if Ultima could heal Lucas.