After the coronation of Isabel, the first marital problems broke out. Fernando believes that Isabel exercises functions that he considers proper to a male monarch and feels displaced.

The personal struggle between them muddies the beginning of the reign and his enemies, particularly Archbishop Carrillo, try to take advantage of their differences. The danger lurks. The fabled nobles ally themselves and resort to Portugal to proclaim their niece Juana la Beltraneja queen.

For many, Isabel has usurped the throne and is not legitimized. She is willing to fight until the end. But first she will have to earn her husband's support and it will not be an easy task.