[1] The film opens with Lucrezia (Simonetta Stefanelli) seeking solace in a monastic retreat while waiting for her marriage with Giovanni Sforza (Aldo Reggiani) to be annulled.

During her retreat, she escapes at night to meet up and engages in a forbidden affair with her brother, Juan (Paolo Malco).

Cesare's (Massimo Foschi) jealousy and paranoia lead to a confrontation where he accuses Juan of defiling Lucrezia, resulting in fratricide.

Haunted by the tragedy, Lucrezia flees from Cesare's oppressive control, navigating a perilous dynamic of fear and longing.

The film culminates in a gripping finale that challenges loyalties and explores the blurred boundaries between love and possession in a family torn apart by dark desires.