A team of researchers has tracked down the cellular origin of cutaneous melanoma, the deadliest form of skin cancer. The team was surprised to observe that these very aggressive tumors arise from mature, pigment-producing cells called melanocytes. As melanoma develops, these cells are eventually reprogrammed, lose their differentiated features and become invasive, migratory cancer cells. This knowledge is vital to understand how these melanoma lesions are formed, facilitate their early detection and develop preventive treatment avenues.