For thousands of years, humans have asked if we perceive the world accurately through our senses. Because seeing is so important for our functioning in the world, efforts to understand how perceptions are generated have most often focused on vision. Based on current research in cognitive neuroscience, this film explores the challenge of explaining visual perception. The production includes an overview of the human visual system, illustrated with animated graphics and live action footage, and it describes, using a series of engaging optical demonstrations, the profound technical and philosophical challenges scientists face in attempting to explain perception. The film ends with a thought provoking discussion of the essential role of human experience in determining what we perceive.