In the 25th century, humans have conquered space. The advent of faster-than-light travel has opened up hundreds of habitable planets for colonization, and humans have exploited the virtually limitless space and resources for hundreds of years with impunity. So complacent have they become with the overabundance that armed conflict is a thing of the past, and their machines of war are obsolete and decrepit. What would happen if they were suddenly threatened by a terrifying new enemy?

After two brutal, bloody struggles for their very existence against implacable alien foes, humanity is victorious, but not at peace. As distrust and accusations consume the political discourse between the two major factions, the Eastern Star Alliance military has already begun executing small raiding missions into United Terran Federation space. The Federation fleet, still reeling from the last war, is in no shape to try and protect its own borders.

Jason Burke was a man hiding from himself in a small cabin high in the American Rocky Mountains when his simple, quiet life was shattered one night by what he first assumed was an aviation mishap. But when he investigates the crash, what he finds will yank him out of his self-imposed exile and thrust him into a world he could have never imagined.

Out of the blue, a young Space Fleet officer's dream becomes reality: He's made captain of a starship. Just in time for the return of humanity's most terrible enemy, after 50 years of peace. To survive against this enemy, Captain Tad Thatcher will have to do more than learn how to become an effective commander, or how to wrangle his wayward crew. He will need to reinvent space combat. From scratch.

Aliens exist...and, as it turns out, most of them aren’t that friendly. Jacob Brown wasn’t even born yet the first time they attacked Earth. He was only 14 the second time it happened. When Earth finally came together and fielded its first spaceborne military, Jacob didn’t hesitate to volunteer. Serving aboard a mighty starship, he’d be able to defend his planet - and his family - when, inevitably, they came again.

In the 20th century Earth sent probes, transmissions, and welcoming messages to the stars. Unfortunately, someone noticed. The Galactics arrived with their battle fleet in 2052. Rather than being exterminated under a barrage of hell-burners, Earth joined their vast Empire. Swearing allegiance to our distant alien overlords wasn't the only requirement for survival. We also had to have something of value to trade, something that neighboring planets would pay their hard-earned credits to buy. As most of the local worlds were too civilized to have a proper army, the only valuable service Earth could provide came in the form of soldiers....

A company of Army Rangers is sent on an interstellar colony ship to secure a foothold on a dangerous, alien planet through violence of action. Leaving behind a warring Earth flung headfirst into a conflict of mutual assured destruction, the Rangers and the accompanying crew of first colonists are guided on a 40-year journey by an unprecedented artificial intelligence. But when they emerge from the frigid embrace of cryosleep, they awake to a nightmare, finding themselves greeted by the same ruthless enemy that brought about the ruin of Earth.

A secret buried in the Antarctic. A puzzle unsolved for thousands of years. And a Brooklyn-born master gunnery sergeant who's royally pissed that he has to babysit the researchers sent to figure it all out. But when Patrick "Wic" Finnegan finally sees what the team has uncovered, he can't believe his eyes, nor is he prepared for the violence to come. Soon, the portal opens and unleashes a storm of unbridled fury upon humanity.

In the wilds of a jungle planet, the Legion fights in brutal combat as Republic marines fly their SLICS from one tragedy to the next. H292, a repurposed warbot, shows the heart of a hero as he wades into the battle not to destroy - but to save.

The Hundred Worlds have withstood invasion by the relentless Hok for decades. The human worlds are strong, but the Hok have the resources of a thousand planets behind them, and their fleets attack in endless waves. The long war has transformed the Hundred Worlds into heavily fortified star systems. Their economies are geared for military output, and they raise specialized soldiers to save our species. Assault Captain Derek Straker is one such man among many.