Tells the inside story of Mohammed Emwazi's journey from an ordinary London boy to becoming 'Jihadi John' - one of the most notorious terrorists ever. It explores the shattered lives of Jihadi John's hostages, and the emotional and psychological turmoil of the family members whose relatives were barbarically murdered by the British terrorist. It also gives the definitive account of the hunt for Jihadi John by CIA, Pentagon and British intelligence operatives who have never spoken publicly about the operation until now. In extraordinary first-hand accounts, the intelligence operatives also reflect on their own failures in the fight against Isis, and interrogate the twisted worldview of 'Jihadi millennials' who have turned social media into recruitment platforms.