In the 1800s, a sailing ship crashes off the coast of Norway. In the 1900s, a Zepellin explores an icy canyon in Antarctica. In the far future, a spaceship sets out for an alien artifact. Each excursion goes horribly wrong. And on every journey, Dr. Silas Coade is the physician, but only Silas seems to realize that these events keep repeating themselves. And it's up to him to figure out why and how. And how to stop it all from happening again.

Noah Harris and Ashley Flynn are field agents for a powerful organization tasked with protecting humanity from the misuse of game-changing technology. But when they discover hidden portals that link Earth to numerous planets, they are thrust into a maze of deception and intrigue they can't begin to understand....one that not only has them battling for their very lives, but that will decide the fate of worlds. Because, inexplicably, each of the planets contain human civilizations, and the rulers of our nearest portal neighbor have come up with a brilliant, twisted plan to conquer ours.

Jack Kernigan is having a bad day...a bad year...a bad life. After being booted out of MIT, he’s back in his Ohio hometown, working for the family business, facing a life of mediocrity. Then one day, out on a delivery, his truck hits...something. Something big...something furry...something invisible. And, it turns out, something not of this Earth. Fate can play funny tricks. Which is why Jack suddenly finds himself the planet’s best hope to unravel a conspiracy of galactic proportions that could spell the end of the human race.

Alexander Grant is a little too good at a few too many things. Two dozen martial arts. Twice that many languages. Chess, the piano, sports, forging excused absences, you name it. He graduated high school top of his class 17 times. Of course, no one knows any of this. Not that he wants to go unnoticed. It’s just safer that way.

After a rough break up, Wyatt moves to New York City, eager to prove himself while working on Wall Street. When he’s asked to visit the father of his ex-girlfriend, a billionaire tycoon, his fate is sealed. The revolutionary company, Nu-En, launches a radical innovation, an energy that will allow every person on the planet access to power. Only it doesn’t perform as anticipated. Harnessing the ocean has consequences, and highly dangerous creatures emerge from the depths. Soon, the Earth is fracturing, and the world will never be the same.

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.

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....

Ryland Grace is the sole survivor on a desperate, last-chance mission - and if he fails, humanity and the Earth itself will perish. Except that right now, he doesn't know that. He can't even remember his own name, let alone the nature of his assignment or how to complete it. All he knows is that he's been asleep for a very, very long time. And he's just been awakened to find himself millions of miles from home, with nothing but two corpses for company.

Idris has neither aged nor slept since they remade him in the war. And one of humanity's heroes now scrapes by on a freelance salvage vessel, to avoid the attention of greater powers. After Earth was destroyed, mankind created a fighting elite to save their species, enhanced humans such as Idris. In the silence of space they could communicate, mind-to-mind, with the enemy. Then their alien aggressors, the Architects, simply disappeared - and Idris and his kind became obsolete. Now, 50 years later, Idris and his crew have discovered something strange abandoned in space.

Hackett, in his trusty ship the Perseus, is not just a space traveller—beginning his travels with an expedition to Neptune and back—but, thanks to the time-dilation effect, a time traveller as well. His new mission will take him to Andromeda, to get a close-up look at the constellation which will eventually crash into the Milky Way, and give humanity a heads-up about the challenges which are coming. A mission which will take him five million years to complete. Not only is Hackett exploring unknown space, but he will return to a vastly different time.

With the help of a powerful computer system, Alison Shaw and her team are preparing to translate the first two-way conversation with the planet's second smartest species. But the team discovers much more from their dolphins than they ever expected when a secret object is revealed on the ocean floor. One that was never supposed to be found.

What would you do if you discovered Earth’s oldest secret, but the very existence of that knowledge meant that you could not safely share it with anyone else? Where would you turn if you had uncovered something so shocking that it could force the entire world to readdress its views of humanity? Gada has always asked questions that no one has the answers for. Only through her studies has she met professors and teachers who are open-minded enough to consider her theories about the true history of humanity.

When an experiment to study quantum uncertainty goes spectacularly wrong, physics student Bill Rustad and his friends find that they have accidentally created an inter-dimensional portal. They connect to Outland - an alternate Earth with identical geology, but where humans never evolved. The group races to establish control of the portal before the government, the military, or evildoers can take it away. Then everything changes when the Yellowstone supervolcano erupts in an explosion large enough to destroy civilization and kill half the planet.

It's 1974, and Jerry Stieglitz is a grad student in marine biology at UCLA with a side gig selling short stories to science fiction magazines, just weeks away from marrying his longtime fiancée. Then his life is upended by grim-faced men from three-letter agencies who want him to join a top-secret "Project Azorian" in the middle of the north Pacific Ocean—and they really don't take "no" for an answer. Further, they're offering enough money to solve all of his immediate problems.

Between 2017 and 2021, the US military admitted to having undeniable evidence that UFOs (now UAVs or UAPs) are here and defy the laws of physics. When Jason Ramsey, a popular science-fiction writer, becomes obsessed with the subject, he undertakes a relentless quest to uncover what is really going on. After recruiting Tessa Barrett, an extraordinarily talented mercenary, Jason devises a risky, desperate plan to get to the bottom of it all. But the truth is far more shocking, convoluted, and dangerous than anyone could have guessed, and he has no idea who he can trust.