There is a small, but growing, group of blind people who are learning to ‘see’ with sound. Similarly to Daredevil the blind superhero, they use sound to ‘see’ the world around. With a lot of practice, they learn to use tongue clicks as flash sonar to paint a mental image of what’s around them. Daniel Kish is blind and has become a master as flash sonar. Now, he teaches other blind people how to free themselves.