Our smartphones hold our secrets - the version of ourselves we may not want to show the world. With extraordinary access to the contents of a smartphone used by three British men who left their homes to go to Syria and fight with ISIS, journalist Mobeen Azhar uncovers what happened to the three men. Mobeen tries to understand their motivations, how they became radicalised and who is ultimately responsible for their one-way journey to certain death. Using previously unseen videos, photos and screenshots from the smartphone, Mobeen explores what made these three men join an estimated 900 Britons who went out to Syria and Iraq to fight with the world’s most feared terrorist group. While much of the media’s focus has been on the schoolgirls who went to join ISIS, a much larger number of the Britons who made this journey were young men. The three men who feature on the smartphone came from very different backgrounds, and one was a private school boy. Reaching out to the people who really knew them, Mobeen pieces together their stories of hope and delusion - a case study in how extremist ideology takes hold of a life.