Pulitzer-winner Warrick ("The Triple Agent" examines the origins of ISIS in this incisive, horrifying, and eminently readable work. Though the group was officially founded in 2006, Warrick traces its roots back to the recruitment of Abu Musab al-Zarqawi by al-Qaeda in 1999. Warrick follows Zarqawias unlikely rise from lowly Jordanian street thug to Afghan mujahideen, to brilliant strategist and charismatic leader. With surgical precision, the author details how a perfect storm of circumstancesa Zarqawias friendship with a noted radical Muslim scholar who was in prison with him, the king of Jordanas sudden death and his sonas reluctant acceptance of the crown, and, most notably and disastrously, the U.S. occupation of Iraqa led to Zarqawias ascent. Readers trying to keep track of the heads of state, CIA operatives, tribal leaders, clerics, and diplomats will be glad for the list of principal characters in the bookas front matter, but theyall rarely need to consult it, thanks to Warrickas firm grasp and skillful explanation of the complicated subject matter. This is an eye-opening read for general audiences seeking to learn more about the current crisis in the Middle East.