This landmark exhibition investigates a virtually unknown period in the career of Leonardo da Vinci, one of the most famous artists of the Italian Renaissance. It focuses on Leonardo’s early years as an apprentice in the studio of the sculptor, painter, and goldsmith Andrea del Verrocchio, seeking to identify the young artist’s hand in paintings known to be collaborations with his teacher and fellow pupils. Rather than relying on the claims of previous scholarship, the exhibition restores the primacy of visual evidence, encouraging visitors to look closely and carefully at works side by side. At the core of the exhibition is a pair of predella panels—The Annunciation, from the Musée du Louvre, Paris, and A Miracle of Saint Donatus of Arezzo, from the Worcester Art Museum, Massachusetts—that once belonged to a large altarpiece, the Madonna di Piazza, in Pistoia, Italy. These works have been documented as a commission to Verrocchio and were supposedly executed by another of his apprentices, Lorenzo di Credi; however, both paintings are, in one case entirely and in the other in large part, the work of the young Leonardo. A selection of sculptures, cassone panels, and other paintings lent by international public and private collections—which have each been variously attributed to Verrocchio, Leonardo, Lorenzo, or other lesser-known artists—offers additional points of comparison, helping to clarify the personality of each artist and shedding light on the depth and nature of collaboration in Verrocchio’s workshop.