After running and gunning across much of the western US, Cade Grayson, former Delta Force operator, is finally reunited with his wife, Brook, and daughter, Raven. Hours after arriving at the relative safety of Schriever Air Force Base in Colorado Springs, the new Capital of the United States, Cade is approached by the new president, Valerie Clay. Her request is simple: she appeals to the patriot in him to rejoin the unit that he left for civilian life 15 months prior and once more go into harm's way, taking the fight to the enemy.

For Cade Grayson, father, husband, and former Delta Force operator, life has changed drastically over the course of 48 hours. He's watched the dead inexplicably return to life before his very eyes. He's lost many people near and dear to him, most dying unfathomably horrible deaths at the hands of the dead who have seemingly overnight taken over the big metropolis - their numbers and hunger for human flesh growing exponentially with each passing hour.

Allegiance picks up two days after A Pound of Flesh left off. Outbreak - Day 15. With an estimated 99 percent of the United States' population having already succumbed to the rapidly spreading Omega virus, and countries and cities worldwide teeming with the dead, the struggle to survive the zombie apocalypse continues unabated in the high desert of Colorado.

As the first waves of injured bystanders, guardsmen, and rioters arrived at hospitals, it became apparent that a deadly new disease had been unleashed on the population. Whether the virus was naturally occurring or an escaped lab experiment, Cade hadn't a clue and wasn't especially concerned until he learned of its unprecedented virulence, unusual method of transference, and the fact that, according to the news, it brought the newly dead back to life, semi-mindless, and with an insatiable desire to feed on the flesh of the living.

Outbreak - Day 16: With an estimated 99 percent of the United States' population having already succumbed to the Omega Virus and been reanimated to form roving hordes of flesh-eating monsters, two groups of survivors struggle against long odds to survive the zombie apocalypse.

Cade Grayson, father, husband, and former Delta Force operator collected his fair share of ghosts as the Omega virus ravaged the United States, turning the majority of her population into mindless automatons hungering for human flesh. Wearing incredulous stares, the faces of those ghosts - dozens of men, women, and children he was unable to save during his many forays into the Z-infested wasteland - visit him nightly during the early morning hours when defenses are dulled and REM sleep has him in its firm grip.

In the three weeks since mounting a brash rescue mission to a zombie-infested Los Angeles and returning home to find lives of loved ones hanging in the balance, Cade has occupied himself with runs outside the wire to procure supplies necessary to ride out what the Farmer's Almanac predicts will be a long, cold winter. As Cade and his team seize an unforeseen opportunity provided by the plummeting temperatures, he quickly realizes they are in a race against time - and nature's fickle whims.

Army veteran Lee Riker is staying in an Atlanta shelter and supporting himself with the odd carpentry job when his sister, Tara, summons him home to Indiana for the reading of their mother’s will. Riker boards a Greyhound bus in Atlanta with his duffel bag, less than $200 to his name, and a secret he must protect at all costs. Riker makes it to Middletown only to learn his sister has recently witnessed a gruesome death. Insisting she saw the victim rise from a pool of his own blood to attack the Samaritan rendering aid, Tara floats the idea that the man may have been a zombie.

Cade Grayson - husband, father, patriot - discovered two undead enemy soldiers on American soil, and soon the official call to duty came directly from the President herself in a transmission beamed by military satellite to Cade's refuge in rural Utah: It was time to take up arms in defense of his country once again. Valerie Clay’s hard-to-fathom video footage, showing thousands of enemy soldiers establishing beachheads all along the West Coast, made it impossible to resist. He was a former US Army Delta Operator and he had to come to the aid of his dying country.

Like a fragile house of cards in a hurricane, Presidents, Premiers, entire governments and their ruling bodies disappeared instantly. Some had ensconced themselves in deep underground bunkers or remained holed up in fortified strongholds, but history would tell that most had been swallowed up by the dead - never to be heard from again. On that last normal Saturday in July, while an unknown virus indiscriminately wreaks destruction and death to all four points of the compass.

Presidents, premiers, entire governments disappeared instantly, like a fragile house of cards in a hurricane. Some hid deep underground or holed up in fortified strongholds, but most were swallowed up by the dead, never to be heard from again. For Cade Grayson, doting father and patriotic Delta Force operator, the past week has been the worst dealt to him by life during his short 35-year stint on planet Earth.

"The Suck" - the virus that claimed 97 percent of humanity - is gone. The arrival of other survivors with a different take on the future may be as dangerous as the virus itself. In the middle, with their hands on the scales, is a group of former soldiers and civilians who survived the virus in Antarctica. They’ve arrived to find a dead world, with no rules. The best-selling story of Jason, Pro, and Rachel continues where End of Summer, book one of the Seasons of Man series, left off. 

Following a successful mission to the nation’s former capital, Cade Grayson - doting father, faithful husband, and patriotic Delta Force operator - returns to the compound in rural Utah to find his life irrevocably altered. Five days later and still reeling from the catastrophic event that pushed him physically and mentally to the edge of the abyss, Cade sets out to fulfill a longstanding promise: escort his daughter, Raven, outside the wire to begin the long process of honing the skills she will need to survive the zombie apocalypse.

Disorder and chaos ravage London when thousands are contaminated by the accidental discharge of an experimental bioweapon. The disease robs its hosts of rational thought, giving them a singular desire - find more living flesh to infect.

When a viral apocalypse kills 97 percent of the people on the planet, the survivors' humanity is hanging by a thread. Amid the leftovers of civilization, ex-Army Ranger Jason Larsen is reminded of the meaning of hope, family, and loyalty by a dog and a young boy who are as alone as he is. The survivors he seems to collect become family, and that is very bad news for those who think they run the apocalypse.