Prince Harry's blockbuster memoir "Spare" is already a runaway success, shattering sales records as readers rush to learn details both salacious and mundane about the British royal's life. 

Though the 38-year-old has been on a media blitz promoting his book in recent weeks, the prince had help piecing together the 416-page manuscript for "Spare" in the form of superstar ghostwriter J.R. Moehringer, who has quietly written a number of other bestselling autobiographies.