When Gina Bianchi returns to the beautiful Italian resort of Portofino to attend her father's funeral, she is beset by vivid memories of World War 2, when she joined the Resistance, alongside her identical twin sister, Adele. In her childhood bedroom, Gina reads Adele's diary, left behind during the war. As Gina learns the shocking truth about her sister, she's compelled to face the harsh realities of her own past.