A 12-year-old child (DI) who was completely blind from birth, made a series of tactual (raised-lines) drawings of cars. Among them, there was the depiction of a 'fast car at night' in which DI drew beams of light projecting out of the car. We analyse this drawing, and the preceding ones. We argue that the way in which cars and light beams were depicted by DI cannot be fully and solely explained by graphic imprecision, executive or motor deficiencies, or by rote or verbal learning. Instead, we propose that the most plausible explanation is that DI's depiction of light in a fast car at night reflects the child's naïve knowledge of light propagation, and that this knowledge was gained through perceiving light as radiant heat.