Terms of Enlistment is the kind of book that makes people fall in love with the Military Sci-Fi. Set in the late 21st century, this first installment in the Frontlines series delivers a grim yet believable future, where Earth is overcrowded, militarized, and deeply unequal.
It’s through this lens that we meet Andrew Grayson, a young man from a welfare slum in Boston, who sees military service as his only shot at escape. The novel starts grounded (literally) in the mud, concrete, and filth of Earth’s Public Residence Clusters. Grayson’s world is one of ration packs, gang violence, and hopelessness. His enlistment into the North American Commonwealth Armed Forces feels like a small personal victory, but what follows is a rapid-fire descent into the brutal reality of boot camp, deployment, and a deeply flawed military machine.
Author Marko Kloos, a military veteran himself, writes with authenticity. The boot camp scenes are tense and immersive, the squad dynamics are realistic, and the tech feels just advanced enough to keep things sci-fi without becoming unrelatable. Grayson’s first real assignment, peacekeeping in a riot-torn Detroit, reads like Black Hawk Down with exosuits and drones. The action is sharp, but it's also morally heavy. Kloos doesn’t glorify violence - he lets you sit in the discomfort of watching a soldier use deadly force on civilians who are just as desperate as he once was.
Halfway through the novel, Terms of Enlistment shifts gears ... fast. After being injured and reassigned to a Navy posting, Grayson finds himself in space, reunited with a fellow recruit (and love interest), Halley. What begins as routine patrols turns into first contact with a terrifying alien force, nicknamed the Lankies. Towering, silent, and seemingly unstoppable, their introduction feels like stepping from gritty realism into survival horror, and it works.
But speaking of flaws, the book isn’t without them. Some readers may notice plot conveniences - Grayson moves through obstacles with fewer setbacks than expected. The world-building is also more surface-level than deeply developed; global politics and entities like the Pacific Alliance are mentioned but not explored in depth. Still, Kloos has addressed this choice publicly, saying he prioritized pacing and character immersion over dense exposition.
So, despite minor issues, Terms of Enlistment excels where it counts: pacing, character voice, and a strong emotional hook. It’s a lean, fast read that keeps you turning pages and sets up a larger universe that continues to evolve in later books and in the new Frontlines: Evolution series (book 2 coming out in August). If you’re looking for a grounded and, I think, accessible entry point into Military Sci-Fi, or you’ve doubted the genre in the past, check out this book!
You can read Terms of Enlistment here.
Watch my full review here:
Yes! Loved it. I need to continue the series sometime. Thank you for this article. I enjoyed it.