John Carney, 42, served six years in the Yorkshire Regiment and did two tours in Northern Ireland. He was a team leader in Iraq with Aegis Defence Services, the multi-million-pound private security firm set up by Colonel Tim Spicer. He has operated a close protection service in Iraq since 2011 and currently organizes deradicalization programmes on the Syrian/Turkish border. To protect his family, the name John Carney is a pseudonym. Names of his family and colleagues have been changed.

Clifford Thurlow has lived all over the world and has worked as a gem stone dealer and a foreign correspondent for the Observer in Athens. The winner of the London Arts Board New Millennium Prize for short fiction, he is best known as a ghostwriter. His recent books include: Making A Killing, the inside story of a hired gun in Iraq, and Escape from Baghdad with Captain James Ashcroft; Fatwa, Living with a Death Threat for Jacky Trevane; and Today I'm Alice for Alice Jamieson.