Discusses the concept of gravity from its earliest recognition in 1666 to the discovery of gravitational waves in 2015, and explains why gravity holds the key to understanding the nature of time and the origin of the universe.

Foreword: Six things you may not know about gravity -- Part one: Newton. The Moon is falling ; The last of the magicians ; Beware the tides of March ; Map of the invisible world -- Part two: Einstein. Catch me if you can ; Ode to a falling man ; Where God divided by zero -- Part three: Beyond Einstein. A quantum of space-time ; The undiscovered country.