A couple of years ago, I read a book that examined the changing nature of war that’s stuck with me. The Modern Mercenary: Private Armies and What They Mean for World Order by former soldier and contractor Sean McFate examines the rise of the Private Military Companies (PMCs) that offer security services to governments, companies, and private citizens around the world. He outlines that they represent a fundamental change in the conduct of war, and draws parallels between the Middle Ages — before a time when the state had a monopoly on the use of force — and our likely future. Technological innovation is a primary driver of this change, with companies using drones, advanced weapons, and the internet to play a role in the battlefield.

This is the world that Linda Nagata vividly portrays in her new self-published novel, The Last Good Man. It’s a frightening and gripping story about a future where private commandos dress in light-altering camouflage, deploy handheld drones to the battlefield, and print up their own firearms. The novel follows Army veteran True Brighton, co-owner of a PMC known as Requisite Operations. The story begins with a hostage rescue in the Tigris-Euphrates Zone — the war-torn future of Iraq and Syria, where radical clerics and warlords wage a continual, grinding war. When the team goes into the region and pulls off a daring rescue, their triumph is cut short when a new player enters the battlefield, one that has ties to Requisite Operation’s owners and mistakes that they made in the past.

Years ago, True’s son Diego was horrifically tortured and killed after a blotched operation in Asia, and as she and Requisite Operations CEO Lincoln Han begin to investigate the reappearance of a former ally, old wounds from his death are ripped wide open. Diego’s death might not have been as straightforward as they thought, and they discover a complicated, geopolitical cover-up that involves militant groups and shady allied militaries. Nagata shows off a terrifying future as their search takes them across the world and into hazy new battlefields. AI-controlled drones engage one another in the skies over Iraq, while secretive governmental programs test swarms of killer robots in Asia. True and her compatriots have plenty of tools at their disposal to operate in this new world, from venomous drones to 3D printers that churn out guns, to programmers who construct the next generation of combat AIs.

Nagata has carved out an impressive name for herself in military science fiction circles in recent years with The Red trilogy: First Light, The Trials, and Going Dark, which followed the actions of a group of soldiers and the rise of a mysterious AI that seems to have some larger purpose for the human race. (Disclaimer: I published a story by her in my own anthology, War Stories: New Military Science Fiction.) First Light earned a Nebula nomination when it was published — a first for a self-published novel — but The Last Good Man takes a slightly different route, looking at the consequences of the loss of government’s exclusive hold on the use of armed force around the world, the rise of easily available military hardware, and the fallout. It’s a world where war is a cheap commodity for working out disagreements or grudges.

While technology is quickly taking over the battlefield, Nagata’s focus never strays from her characters. True is an impressive woman: a 49-year-old mother who left the military when her job as a pilot was made obsolete by autonomous helicopters. She contends with not only threats on the battlefield and workplace, but how her job and past wreaks havoc with her family. True’s backstory and the death of her son Diego play a pivotal role in the new threat that she and Requisite Operations face, and getting to the bottom of it becomes an obsession that threatens everything she’s worked for. Technology might be changing the battlefield, but it’s still human relationships and problems that drive the need to go to war, whether it’s a government or private company waging it.

The Last Good Man is a fantastic, lightning-fast thriller that hits all the right notes: an engaging story set in an all-too-plausible future, advanced technology, plenty of action, and fantastic, well-rounded characters. It’s a chilling look at where we might be headed, and hopefully, it’s a future that will remain as a story, rather than a road map of what’s to come.