The twenty-sixth century. Humanity has expanded beyond Earth’s system to hundreds of planets that colonists now call home. But the United Earth Government and the United Nations Space Command is struggling to control this vast empire.

This is the electrifying origin story of Spartan John-117—the Master Chief—and of his legendary, unstoppable heroism in leading the resistance against humanity’s possible extinction.

2552. Having barely escaped the final battle for Reach against the vast alien alliance known as the Covenant, the crew of the Pillar of Autumn, including Spartan John-117—the Master Chief—and his AI companion Cortana, is forced to make a desperate escape into slipspace. But their destination brings them to an ancient mystery and an even greater struggle.

2552. The theocratic military alliance known as the Covenant is showing no mercy as it continues to assault every human world it encounters, but in the way lies humanity’s greatest champion, the super-soldier Spartan John-117—the Master Chief.

The twenty-sixth century. Once considered clandestine, the Spartan-II program has now gone public. Tales of armored super-soldiers fending off thousands of Covenant attacks have become the stuff of legend. While the Master Chief defends a besieged Earth, and the myriad factions of the Covenant continue their crusade to eliminate humanity, an ultra-secret cell of the Office of Naval Intelligence known as “Section Three” devises a plan to buy the UNSC vital time. It will need hundreds of willing soldiers, though—and one more Spartan—to get the job done.

It is 2553, and the three-decade long Covenant War that defined a generation has suddenly drawn to a close. Yet, in the remotest parts of human space, tensions remain that threaten to overflow into another full-scale conflict.

Also in The Ferrets trilogy:

Find. Claim. Profit. In a post-war galaxy littered with scrap, it’s the salvager’s motto. And with a fast ship and a lust for adventure, Rion Forge has certainly made her mark on the trade. When the discovery of a wrecked UNSC cruiser brings Rion’s past back to haunt her, stirring fresh hope into a decades-old wound, she’s hell-bent on finding answers: What really happened to her father and his ship, the Spirit of Fire?

Also, in Rion Forge & ACE OF SPADES:

2526. It has been a year since humanity engaged in its destructive first contact with a theocratic military alliance of alien races known as the Covenant. Now the hostilities have led to open war, and the United Nations Space Command understands virtually nothing about its new enemy.

More Master Chief & The Blue Team:

While Spartans get all the glory, no soldier―not even the legendary Master Chief―wins a war on his own. Gunnery Sergeant Edward Buck and his team of Orbital Drop Shock Troopers (ODSTs) played a major role in saving Earth from all-out invasion at the end of the Covenant War―acts of bravery and ingenuity that did not go unnoticed by the United Nations Space Command.

But is it time for Buck to retire to the sidelines for a life he could only dream about…or is he prepared to step up and become part of the military’s new blood?

Just hours following their climactic battle on the Forerunner planet Genesis, the Spartans of Blue Team and Fireteam Osiris find themselves running for their lives from the malevolent machinations of the now-renegade artificial intelligence Cortana. But even as they attempt to stay one step ahead, trouble seems to find Spartan Edward Buck no matter where he turns.

2535. It is the first, desperate days of the Human-Covenant War, and the United Nations Space Command has enacted “the Cole Protocol” to safeguard Earth and its inner colonies from discovery by its merciless alien foe. Among those tasked with eliminating any trace of such dangerous information is Navy Lieutenant Jacob Keyes—now saddled with a top-secret mission by the Office of Naval Intelligence…one that will take him to a corner of the galaxy where nothing is as it seems.
 

It has been six years since the end of the Covenant War...and yet on the planet Carrow, a world on the edge of the Joint Occupation Zone, a decisive new battle suddenly erupts. And none can anticipate the ongoing violence leading to the discovery of an even greater, unstoppable threat—one hidden for eons below the surface of the planet….

One hundred thousand years ago, the galaxy was populated by a great variety of beings.

But one species—eons beyond all others in both technology and knowledge—achieved dominance. They ruled in peace, but met opposition with quick and brutal effectiveness. They were the Forerunners—the keepers of the Mantle of Responsibility, the next stage of life in the Universe’s Living Time.
And then they vanished.

This is their story.

Also in the Forerunner Saga:

This collection of eleven stories dives into the depths of the vast Halo universe, not only from the perspective of those who fought and died to save humanity, but also from those who vowed to wipe it out of existence.

Halo: Fractures explores mythic tales of bravery and sacrifice that blaze brightly at the very heart of the Halo universe.