Sleep — one of the crucial determinants of health is also a biological and psychological mystery. Writer and broadcaster, Jeff Warren takes us on a two-CD adventure into the world of sleep and dreams. Jeff slept the sleep of our ancestors enjoying the pleasant awakenings between what they called their first and second sleeps of the night. He also learned what it takes to control what happens in our dreams in a lucid dreaming workshop. He met the first ever historian of sleep and the first anthropologist to study sleep in its natural state. And Jeff found out first hand what researchers are learning about what your brain has been up to while you were out.