The explosive true story of life in MI5 from the number one bestselling author of Soldier Spy, Tom Marcus. 'One of the most successful MI5 undercover surveillance officers of his time.' - Sun 'Secret wars fought by heroes who seek no reward. A brilliant read written by a true legend' Ollie Ollerton 'A massive operational insight into the war fought on our streets' Jason Fox Tom Marcus spent years of his life working covertly against those who want to do us harm. Now, for the first time, he tells the full story of what it is like to live your life in the shadows and who you need to become to survive. First published in 2016, Soldier Spy was a series of stories from Tom's years in MI5 and has now sold over 250,000 copies across all editions and was a Sunday Times bestseller for five months. I Spy takes us deeper into his life as a spy.