Martin McKenzie-Murray's new book, Sirens, is an intimate and remarkably powerful portrait of three first responders – a paramedic, a police officer and a firefighter – who are motivated by a desire to serve the community, but they are drawn to their work by more complicated impulses as well. In telling their stories, McKenzie-Murray draws on his own experience and his research into trauma and recovery to ask profound questions about human motivation and survival. Here he talks to Nick Feik about the research and writing of his book.

McKenzie-Murray is The Saturday Paper's associate editor, and a two-time Walkley finalist and winner of the Melbourne Press Club's Quill Award for commentary. He has worked as a teacher, speechwriter, columnist for The Age and adviser to the chief commissioner of Victoria Police. His first book, A Murder Without Motive, was shortlisted for the Ned Kelly Awards for crime writing. His second, The Speechwriter, won the Russell Prize for Humour Writing.