Science Fiction Time Travel

A formidable alien armada stands on the brink of vanquishing the cosmos, their gaze set firmly on every inhabited world. The last line of defense? An eclectic crew of improbable champions: a maverick starfighter pilot, a daredevil stuntwoman, a lethal super-assassin, and a cosmic prankster with alien tricks up his sleeves. Their mission is to shield not just humanity, but billions of other intelligent lifeforms spanning the multiverse.

Nyx was born Hollow. An empty vessel in a world of spirits. Normally, that was a death sentence, yet somehow he survived. He's always been stubborn like that. He's also always been a bit crazy. Which is why, in another life, he did something reckless. He sent himself a message—his memories. Threw them into the Flow from which all spirits return. Besides, Nyx believed in asking hard questions. Like, was reincarnation real?

Determined to save the antiques store she has inherited from ruin after the unexplained disappearance of her parents, Sarah Lester discovers a jumbled collection of vintage postcards that leads her on a journey through time. Unprepared for the story the postcards weave about their reclusive former owner, Sarah’s life is thrown into disarray as she is transported to Victorian London, colonial New Zealand, and to the British Raj in 19th-century India.

To say Jon Ryan's life was good would be a silly understatement. Sure. Come on, he did CPR on his very first girlfriend, Jenna, when they were in their tweens and narrowly saved her from drowning. Then they dated throughout high school and were only temporarily separated when he went off to the USAF Academy and she to UCLA. But their future was looking so bright they both needed welding goggles. But, way back there in the reality that seems to always kick anyone named Jon Ryan in the ass was...er, an uncomfortable truth. His life, Jenna's life, and their life together never happened.

In The Knight at Dawn, Jack and Annie find peacocks for dinner and boys in skirts when the Magic Tree House transports them back to the Middle Ages for another wild adventure. In this second book in the series, inquisitive, notebook-carrying Jack and his animal-charming younger sister, Annie, find themselves in the middle of an enormous castle. They can hear the beginnings of a feast under way in the Great Hall.

Travel to other planets is now a reality, and with overpopulation stretching the resources of Earth, the necessity of finding habitable worlds is growing ever more urgent. There’s a problem though—because the spaceships are slower than light, any communication between the exploring ships and Earth would take years.

Tom and Pat are identical twin teenagers. As twins they’ve always been close, so close that it seemed like they could read each other’s minds.

For decades, the singular and provocative paintings by Cree artist Kent Monkman have featured a recurring character—an alter ego of sorts, a shape-shifting, time-travelling elemental being named Miss Chief Eagle Testickle. Though we have glimpsed her across the years, and on countless canvases, it is finally time to hear her story, in her own words. And, in doing so, to hear the whole history of Turtle Island anew.

A military unit is thrust back into Paleolithic times with only their guns and portable hardware. Ten soldiers on convoy in Afghanistan suddenly find themselves lost in time. Somehow they arrived in Earth's Paleolithic Asia. With no idea how they arrived or how to get back, the shock of the event is severe. They discover groups of the similarly displaced: imperial Romans, Neolithic Europeans, and a small cadre of East Indian peasants.

Four years after the Nihil and the Order has a new threat. A clay tablet is discovered at an excavation in Knossos, Crete. The text is written in a language that no one can decipher, but the Nazis have come to claim it and Napoleon sends his own Savants Temporal to the Minoan tomb. Meanwhile, something ancient is infecting the descendants of the great houses of Europe. Book four in the best selling Infinity Engine series.

Seventeen-year-old Aimee Roh has Sensory Time Warp Syndrome, a rare condition that causes her to time travel to a moment in her life when she smells something linked to that memory. Her dad is convinced she’ll simply grow out of it if she tries hard enough, but Aimee’s fear of vanishing at random has kept her from living a normal life. When Aimee disappears for nine hours into a memory of her estranged mom—a moment Aimee has never remembered before—she becomes distraught.

Caitlin has disappeared and someone has changed history. Lost in an alternate reality, Josh must discover who has disrupted the timeline and try to fix the continuum. But there's a problem. The Order has become divided over an old manuscript which describes the Maelstrom—a chaotic realm filled with ancient gods that exists outside of the timestream. One faction believes that Josh will be the key to unlocking its power, the other that he needs to die to save them from oblivion. Josh must find Caitlin and a way into the maelstrom, discover the author of the book and rewrite the prophecy.

When the first humans came to settle the planet Pern, they did not come alone: intelligence-enhanced dolphins also crossed the stars to colonize Pern's oceans while their human partners settled the vast continents. But then disaster struck. The deadly silver spores called Thread fell like rain from the sky, and as human colonists' dreams of a new, idyllic life shattered into a desperate struggle for survival, the dolphins were forgotten.

Matt found a way to erase his past regrets. He was an average guy who was pissing and moaning his way toward retirement. Like many people before him, he often wished things had gone differently for him. Be careful what you wish for!

On their way to fight in the Mexican-American War, a group of American soldiers are swept away to a strange and deadly alternate Earth in this thrilling new adventure set in the world of the New York Times best-selling Destroyermen series.

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.

Fourteen-year-old Nephele used to have friends. Well, she had a friend. That friend made the adjustment to high school easily, leaving Nephele behind in the process. And as Nephele looks ahead, all she can see is three very lonely years. Nephele is also a whip-smart lover of math and science, so she makes a plan. Step one: invent time travel. Step two: go back in time, have a do-over of ninth grade, crack the code on making friends, and become beloved and popular. Does it work? Sort of. Nephele does travel through time, but not the way she planned - she’s created a time loop.

Lise Adams is a young woman attempting to uncover the mystery of her father's disappearance ten years earlier. Turk Findley is an ex-sailor and sometimes-drifter. They come together when an infall of cometary dust seeds the planet with tiny remnant Hypothetical machines. Soon, this seemingly hospitable world will become very alien indeed--as the nature of time is once again twisted, by entities unknown.

Almost a year has passed since Stella and Tom discovered a time tunnel and travelled to early 1900s London, where they befriended Emma, Lucy ,and Jack. The magical moles that made the tunnel and secret lake appear have since vanished, but the children are longing to meet again. Then an illness, which puts Emma’s life in danger, changes everything. The moles reappear, just when needed, and Lucy realizes the only hope of finding a cure lies in the future.

During the test flight of a prototype faster-than-light craft, Lt. Commander Ky is flung into an ancient past that never existed. Rome has fallen, defeated by the mighty Carthaginian Empire, its survivors chased off the continent and onto what had been the remote province of Britannia. Hounded by the Carthaginians bent on conquering the known world, Rome is on the verge of destruction. Stranded and alone, except for a tactical AI implanted in his head, Ky has lost everything and must find a way to live in a world different than anything he's ever known.

Seventeen-year-old Molly's recurrent nightmares become waking visions after she nearly drowns at a party. Soon she's witnessing events through the eyes of a girl who lived in her father's house nearly a century before.