“Ramón y Cajal: drawings on the retina” is a documentary about the Nobel Prize winner that explores, from a contemporary perspective, his fascination with images as a bridge between the reality of the physical world and that created in the brain, with a new integrative approach to his artistic and scientific facets and his legacy, told through the experiences and points of view of researchers, artists, historians, family members, and other experts who consider Cajal a visionary who transcended his own science. In one of the laboratories, a machine answers Cajal's last question: how are images formed in the brain?