Title: Soldier Spy 
Author: Tom Marcus 
Publisher: Michael Joseph/Penguin Random House UK 
Pages: 326 
Price: Rs 699 
In today’s world of uncertain and unexpected violence, an implacable enemy, with thoughts of spectacular mass murder on their minds, may be next to us without we even suspecting their presence or intentions — and our very homes, public spaces and transport are the new battlegrounds. Who can we depend upon to protect us? 
Just a handful of men — and women — whose original remit of unmasking traitors and preventing enemy agents from stealing national secrets, has expanded to supplement police’s efforts to track and foil terrorists planning to unleash mayhem on the streets. Though less glamorous than their counterparts working overseas, the secret security services are an equally vital part of espionage and national security and their work no less exacting or lethal. 
And how exactly they work, with long and uncomfortable stakeouts interspersed with high-speed car chases — and ceaseless observation in the shadows of ever-present personal danger from targets as well as other threats — is told in this high-octane, engrossing but visceral account by a former operative of Britain’s MI5. 
And Tom Marcus cites that old yardstick of terrorism, where the security service have to be lucky every time while the terrorist has to be lucky just once. 
The MI5 describes its employees as “ordinary people, who do extraordinary things”, with “a very strong ethos of public service” despite knowing “their work often goes unnoticed in the public domain”; as people “intensely committed to keeping the country safe”, and who are “tirelessly professional and ethical in the way they conduct their work”. Marcus met the parameters — some more than his colleagues — and a little too well. 
“Some people join the service out of a sense of duty, some out of wanting to do some good by removing the evil. I did it because it’s all I knew. I’m a hunter of people and I’m damn good at it,” he says. 
And this he seeks to prove, as right at the onset, he recounts one key operation, in which he, dressed in urine-smelling rags, tries to keep vigil on an Islamic radical planning mass murder at a local school. He also uses this episode to underline how his service is different from the police, both in methods and objectives. 
For the first, he tells us that “the people we hunt never know we’re there, and even when they end up in court they still don’t know how they got caught”. Their aims diverge, for “police like to arrest quickly, to remove the threat to the public as soon as possible” while his service knows that this “doesn’t defeat the problem, it merely takes away one of the foot soldiers” and they want to roll up the whole network not only take “this one attack out of the equation” but use it to “identify, and stop, ten others”. 
And Marcus shows what kind of demands it makes on the operatives, with one incident where he, out shopping, is on the verge of killing a man behaving suspiciously before he realises that the crime he observed is not the one he was trained to curb. 
In this account, which has been cleared by his agency and thus liable not to reveal to much operational secrets, Marcus not only provides us with a ringside view of their missions, mixing their pursuit of Islamist terrorists — on which he provides an apt perspective — with those of the various Irish splinter groups and Russian and Chinese spies, but also the perils and the moral ambiguities in their work where they only know a bit of the picture and some orders may seem puzzling (the ISI pops up here). 
He is also candid in showing how keenness and dedication lead him to some rash actions, over-aggression, unflagging commitment that eventually led to nightmares and a condition where he could no longer go on. 
An incisive view of some of the leading security challenges before democratic states, Marcus’ account — and especially his fate — is also an unvarnished and uncomfortable look at the means used to counter them and the costs they take on the combatants. It is also a captivating account that leaves any espionage fiction far behind.