The story is laid in Italy, during the 17th century, and concerns itself with the love and suffering of David, a great painter. Unknown to David, his betrothed has a brother in prison, and his shame is kept hidden for the honor of the family. This brother, escaping from his cell, goes by night to his sister's room. David, coming to serenade her, sees the brother leave her window; thinking her false, casts her off, and she is too proud to tell him the truth. David, heartbroken, goes to a monastery to seek refuge from the world in seclusion. While there, he learns the truth. A great revulsion of feeling takes place in his heart. A mock sees his grief and begs him seek solace in painting a masterpiece for the altar. This he does, but is stricken to the heart. Gianetta on her way to church sees him weak and ill, crossing the plaza. She follows to his studio in the church. There they come to understand each other, but too late.