After the death of the Medici patriarch, son Cosimo takes charge of the family's widespread banking and assumes a large role in Florence's politics and culture. A rival family faction the Albizzi maneuvers to have him taken out of the way.
Medici supporters in the draft for the Signoria allow the exiled Cosimo to return and to ally with the also exiled Pope. A Curia member ,Leon Battista Alberti is drawn to the sculpture, painting and building going on in thriving Tuscany.
As Cosimo's political story recedes into the background ,the role of the humanist Alberti in championing new inventions,and in stressing the need for all artists to study nature and mathematics moves into the foreground.