In 1932, world-renowned physicist Wolfgang Pauli had already done the work that would win him the 1945 Nobel Prize. He was also suffering after a series of troubling personal events. He was drinking heavily, quarrelling frequently, and experiencing powerful, disturbing dreams. Pauli turned to C. G. Jung for help, forging an extraordinary intellectual conjunction not just between a physicist and a psychologist but between physics and psychology. As their acquaintance developed, Jung and Pauli discussed the nature of dreams and their relation to reality, finding surprising common ground between depth psychology and quantum physics and profoundly influencing each other's work.