A word of advice: never read Philip K. Dick before going on vacation through time. 

 Did you know the Earth formed through planetary accretion during the formation of the Solar System approximately four-point-five billion years ago? 

 About four years from now, most of the human race will be wiped out by a plague, a virus. We know it’s because of a man named Leland Frost. I have to find him. 

 Did you see the tape at your seventh birthday? I think we already did build it. 

 “Quick,” he shouted. “What year is this?” 

 Which word don't you understand? Time or travel? 

 Time Turner actually did pretty well with her power until she accidentally let slip . . . 

 This bead marks the moment you told Tom Merchant (high on your first-ever vodka shots and the teeth-jittering adrenaline of being out—even just as part of a group—with Tom Merchant, the most brilliant, amazing guy you’d ever met) that you couldn’t care less about your practical engineering major, that thing that your parents were both so proud of. 

 He looks at me, looks at my look, looks at his bag, opens his bag, looks in his bag, takes out a gun. He does not look as if he is about to use it. Instead, he breaks it open. “Look!” he says, and I am looking already. “It hasn’t been fired! How can Princip have laid his hands on another gun so quickly? The car went by thirty seconds after I stole this from his pocket. He didn’t have time! How is it possible? 

 I picture you standing in the kitchen downstairs, over a century ago. I imagine that you’re staring out through the little window above the sink, your eyes traveling down the path that leads from the back door and splits at the creek; one trail leads to the pond, and the other leads to the shelter and the anachronopede, with its rows of capsules and blinking lights. 

 Oh. Oh God. Oh God. Oh God. Oh God. Oh my God. Holy Mother of God. Oh. Oh. Oh. Oh God. 

 Just push me back. 

 I didn’t turn around. Who wants to see an older, uglier version of himself? 

 We scanned her I.D. and it showed she had medical insurance. Otherwise, the rule is that we treat you for the injuries, but there’s no swap. 

 And I’m Jermey when he was in the fifth grade. 

 Okay. But to get to the point, Castoroides ohioensis was a giant species of beaver that lived during the Pleistocene epoch. It’s been extinct for at least ten thousand years. Our project requires sending an animal-capture expert to the late Pleistocene to catch an ohioensis and bring back tissue samples. 

 Not entirely true. Georgie had traveled, two-three times to Kansas City. Hadn’t liked it much: fair enough. It hadn’t liked him, either. Been to Joplin a couple times to visit a sister; to Fort Scott once, to have a special piece of metal crafted for his time machine. That was it. 

 Hackerman: I was able to triangulate the cell-phone signal, trace the caller: His name is Adolph Hitler.
Kung Fury: Hitler. He’s the worst criminal of all time.
Hackerman: You know him, sir?
Kung Fury: I guess you could say that. In the 1940s, Hitler was a kung fu champion. He was so good at kung fu that he decided to change his name to Kung Fuhrer. 

 That radar is more advanced than anything the Germans are using at this point. 

 I regret to inform you that I will not be attending your reception, scheduled for 12:00 UT, 28 June 2009. 

 The scientist who brought it here is dead. His grave was the first one you dug behind your house. 

 Once, we flew back in time. We had breakfast twice that day. 

 Barry: Cyd, when that laser blasted Reynaldo, it was set at two. You guys were blasted at four . . . hundred. [laugh track] There is no telling what could have happened. It could have sent you to another dimension or made you time travel or rendered you invisible.
Cyd: [Sticks finger in mouth. Makes popping noise. Threatens Barry with slobbered-on finger.]
Barry: You’re not invisible. [laugh track] 

 Amy plus Six: Amy, it’s me . . . you, I time traveled from six years in the future.
Amy: How does that work?
Amy plus Six: I don’t know! How does electricity work? You just pay for it. Now listen, five-years-in-the-future-you is gonna come back and talk to you.
Amy: Wait, I thought you were from the future.
Amy plus Six: I’m six-years-in-the-future-you. Five-years-in-the-future-you has bangs. Now, she’s gonna come and she’s gonna tell you—
Amy: If I should get bangs or not?
Amy plus Six: No! Shut the f*** up! She’s gonna tell you not to move in with Travis?
Amy [devastated]: Why not?
Amy plus Six: Because he cheats on you; he gives you gonorrhea and bed bugs. It’s a nightmare.
Amy: Oh, God, I’ve never had bed bugs before. I won’t move in with him.
Amy plus Six: Oh, no no no. You have to move in with him, okay? It turns out that by being warned to break up with Travis that things in the future get really screwed up, and California is now in the ocean.  

 On their way, the Force had discovered the time gates, a pair of artificial wormholes connected across eleven years of time. All the ancient wormholes were incalcuably valuable; their possession was the defining feature of the patron nations. Finding a wormhole was the Union’s chance to slip from beneath the yoke of the Congregate. 

 Then he pulled out the recently engraved Time Law Charter and lingered on it, his fingers brushing the inscriptions. He had found what he was looking for. 

1. Watch The Terminator.
2. [optional, but recommended] Watch T2.
3. Suspend all questions about how various timelines can mesh.
4. Enjoy Genisys.
5. Bonus points if you can identify the other excellent time-travel movie with a main character named “Pops”! (Yes, it’s in my list.)

 Come with me if you wanna live! 

—Sarah to Kyle Reese

 “You see, Inspector,” he says, looking me up and down like I was dressed up for Halloween, “we are not permitted to adjust local-time affairs, for the simple reason that laws vary with time. The legal or moral, I am sure you understand, is a matter not only of place but also of time.” 

 Editor’s Note: This is a work of fiction. Please don’t attempt time travel in this way. 

 Okay, listen you two: We froze time for a pretty long time, so when I unfreeze it, the world’s time is gonna be fine, but our time is gonna need a little time to, you know, stabilize. 

 Well, maybe not everyone. 

 This day, the next hour, were the reasons he had built the device. Not so that graduate students in religion could travel back to Christ’s cruxifixion to see if it really happened as the Bible said. Not so that historians could add to their dissertations by actually speaking to Thomas Jefferson. Not so that techs could fruitlessly try to modify the device so that someone could finally shoot Hitler. 

 She’s wearing a cocked hat of beaver fur over a red waistcoat. Her boat just arrived at a northern city on the Baltic, under a sky of zinc marred by sooty clouds. 

 They became to society as pagans are to us. Considered mad but harmless they were left to their own devices, forgotten for over a century. 

 This Commander Parsec show is pretty ridiculous. The commander is always rescuing bimbos and defeating the bad guys all over the Galaxy. 

 Uh, I really don’t have time to explain right now, but I’m you from just a few minutes in the future. 

 I’m building a time machine, so I don’t have to wait. 

 What’s time travel like? Where’s Hiro? 

 Mother had gone on ahead, Ancesters only knew where. So there was no way forward. But somewhere in the starlit hours of the past—somewhere in the days when the Citadel still existed, and Bright Princess Ngoc Minh’s quarrel with the empress was still fresh and raw—Mother was still alive.
There was a way back. 

 What will become of me? 

 A child doesn’t fully mature until it self-consciously overcomes the mistakes its parents and its community made in raising it. What we are doing is saying to our ancestors, ‘Here and here you were wrong. We refuse to accept these errors. We are taking command of our own history.’ This is part of the maturing of human culture. 

 Will this whole dream last through all that drive and any time after they get there? Is he losing it, maybe, the way Niamh is? Are they both lying in a mortuary somewhere, dead and cold, and this is some kind of afterlife? Has time been changed somehow, so he can do better for her this time around? Jesus, would that even work? Could he be better. do better, given the chance? 

 But first let’s get things rolling by introducing an incredible invention of mine that I like to call the WABAC machine. 

 When questioned what speed he was doing, the driver stated that he was doing 88 miles per hour. 

 What do you think? Your machine is broken. It’s spitting you out, over and over. You’re coming out in groups so you always add up to a prime number. We had seven. Now it’s eleven. 

 Protesting that he was “put up to the whole thing” by a local gang, Martin McFly, Junior, 17, was arrested for the theft of an undisclosed cash amount by Hill Valley Police this morning. The theft, which was accomplished with a stolen degaussing unit, took place at the Hill Valley Payroll Substation on 9th Street at exactly 1:28 A.M. this morning. 

 I substituted phase-compensating lenses to dispel the zero average of the cosine function mandated by Eberhard’s proof. I instituted an autocidal-prevention mechanism to avoid the self-canceling paradox. Kill my own grandfather? Father a child who will bear a child who will kill me? What nonsense. My calcite crystals generate superluminal tachyons. Information from the future! The Nostradamus Machine! 

 Dutton nudged forward, arm shaky, stick wobbling, and when the tip pierced the surface, he was caught unawares by the forceful tug from the other end. He didn’t let go fast enough, stumbling forward, falling into it with two faint words whispering in his mind: Jess . . . Lucy . . .  

 The conversation I was having was déjà vu, but at the same time I was already into tomorrow, and back to earlier in the evening walking up Marty’s porch, looking at the huge Om symbol on the psychedelic tapestry that curtained his window, 

 If I remember right, I don’t have much time, so let me get to the point. What’s really hard to understand is whether or not you can change stuff. 

 You can’t change history, dude. Known fact. You can’t mess with things. Create paradoxes. You could much everything up so you don’t even exist, like in Back to the Future. And, like, every time travel story known to man. You shouldn’t even be telling me this. 

 Time reversed, dragging at my atoms like a boat suddenly throwing down its anchor whilst traveling at full speed. Nausea and vertigo twisted about, dancing just beyond the perimeter of my mind before slamming into my chest and driving the air out of my lungs. 

 I boot up my laptop and search for an old report I got on Jeff when he first started coming in. A report from the future. We call it an insight document. And it tells us everything we need to know about the future of our clients. 

 It’s an escape, of sorts. But . . . but not outward. 

 Pulling back the tarp, I exposed a chromed grill and red paint. Peeling it back fruther, careful not to drap the tarp and bugger up the finish, I found more chrome, more red paint, and red vinyl upholstered seats. As I uncovered more and more of the car, a vague feeling of familiarity crept over me. 

 Five years later, on September 1st, 1980, just after midday, I ceased to exist for a second time. There was no flash, no blinding light or thunderouse drama. No perfect sphere of swirling lightning. I just blinked and everything changed. If I remember it right, on September 1st, 1990, which is where I was when I next opened my eyes, it was raining. 

 What followed were twenty pages of neatly written text intertwined with drawings, sketches, and mathematical formulas. Then several pages with lists of materials. 

 Mostly the job is scratching stray seconds and the occasional minute out of the rigging, sucking up a misplaced nanosecond that somehow got into the cockpit. 

 I was in the way back. Far, far back. I skipped downtime and uptime, back to my past and then up to my home, and everything worked find. Then one day, in the far back, I tried to go home. 

 Thanks for reading these instructions and enjoy the creation and operation of your new universe. With luck, your creation will go on to give you many billions of years of entertainment and pleasure. 

 I call the process “Revival.” I usually go back between one and five minutes. 

 I like being part of a team, man. 

 What you have to do to traverse a wormhole is have two openings. What we did tonight is open one end of it. 

 “There is no Time machine,” it says. “We are not supposed to be here but our Time line pinched and we are in big trouble unless you can help.” 

 You’re going to feel apart from other people. That doesn’t go away. 

1. Married women—Fiction.
2. Physicists—Fiction.
3. Quantum theory—Fiction.

 He can read her face, and can tell that she agrees the opinion that he himself is too politic to speak aloud: that the papers being delivered today are not that good. They are not very interesting. They are parsimoniously doled out fingernail parings of thought, bloated into full length by badly written prose and extensive recapitulations of material with which an audience of this kind would already be familiar. They are evidence that the desire to bide one’s time in order to do good science has be sublimated to the constant drive to publish; as the saying goes, the committees that hand out funds and grand tenure cannot read, but they can count. 

 No-ma-chine! No-ma-chine! 

 He is an old man at her birth, a youth at her third birthday party, and a fifty-something when he walks her to her first day of kindergarten. 

 Dad, do you think time travel is possible? 

 What should you do if a mosasaur comes up out of the sewer and into your bathroom? 

 His story was ridiculous, but he really did look like me plus twenty years, and he knew things about me that nobody else could know. 

 Coulson: Like, in Terminator, if John Connor’s alive and able to send his friend back in time to save his mom to make sure he’s born, doesn’t that mean he doesn’t have to?
Lincoln: I, uh, never saw the original Terminator.
Coulson: You’re off the team. 

 My father set a time trap? 

 Of course, that thought immediately slipped her mind when she turned on the news and saw the main story for the day: time travel had been discovered. 

 Jim: We have a time machine. We have a time machine! None of this has to happen, okay? Somebody goes back and they warn us not to come. So whoever the killer is, he doesn’t get to kill anybody, not today.
Bubbles: Yeah, that’s good.
Gale: Yeah.
Randy: No, we can’t do that. We’ll cause a paradox! 

 It’s not a game, and it’s not a dream. I can time-travel. Clint can. Bruce, too, when he’s not writing on the ground, and apparently so can you. 

 The past is written; the ink is dry. 

 Those who cannot remember the past are condemned to repeat it. 

 We’ve got a reactant coolant leak! 

 Correct, little algorithm, but we are not in your present. We transmitted ourselves by tachyons into the past, back into the stelliferous period, to one of the first galaxies. We have been working here in the morning of the Universe for twelve million years. 

 “The odd ones from the future and the past,” she said, matter-of-factly. “The ones who taught us that the past and future are not one simple path but more like a basket full of loose threads. And all these threads are strung together with different starting points and different events, like knots, along the threads.” 

 Ruptures in space time . . . quantum [gobbledygook] . . . not linear. 

 . . . and a grandmother of three writes her suicide note in the same room that Helen is talking to her therapist, who says that the human mind is a primate one, that we are drawn to the exciting and the new and gloss over the day to day lest we go insane in the details, and the first mammals crawl into and from the trees . . . 

 The Bush bust passed through the vortex, catching fire through friction as it shot through time. 

 Do not worry if one of your quantum selves accidentally “kills” your grandfather in a lovers’ quarrel over your grandmother’s affections. Remember, when the wave function collapses, only one of your selves will be “real.” Simply reset your parricidal self and move on. 

 “We exist within a glitch of the space-time continuum,” he said, hands flailing, “and are doomed to relive this exact moment, this exact conversation, forever.” 

 I felt like something was being stripped away from me. From inside. Like something was being unwound. I don’t know it that’s the right way to explain it. I couldn’t explain it. It was just one of those feelings without a name. 

 The mists are time itself, or at least time as it exists here. 

 ♫If I had my time again, I would do it all the same, they say, but that’s insane—surely you’d want to make a couple of fixes!♫ 

 You have a time machine and you’re not doing anything important or helping anyone. All you’re doing messing with me. 

 I am the most powerful witch in the world, and you are armed with a snowball. Do you know what that means? 

 I already tried that. 

 Faster than light travel makes it possible to send an observer out and back before he left. 

 Lucy? What the hell has gotten into you? And who’s Amy? 

 When all was quiet, he walked into the future in his dreams. He saw these Turtle Men at a village like his mother's, perhaps his mother's village. All villages met the same fate. 

 Two months earlier, the time traveler had appeared, and taught Leo the mourner’s Kaddish. 

 The closest I can come to the giant spider’s name is Mmdhf. She loves to talk philosophy. 

 We, the last and broken memories, vow to undo the errors of our ancestors, to make the Earth whole, the lost unlost, at the peril of our own birth. 

 Perfection, of any kind, was an error. 

 Or is it the first— 

 He’s a human freak as far as I’m concerned. Whatever I think of him, it doesn’t affect my work. 

 Nearly every object of art and entertainment is different in thisworld. Early on, the variations aren't that significant. But as the late 1960s gave way to the vast technological and social leaps of the 1970s, almost everything changed, generating decades of pop cuylture that never existed—fifty years of writers and artists and muscians creating an entirely other body of work. 

 Offered for private sale is a gold watch engineered to allow the discriminating Gentleman the opportunity to experience time in a new way. This is a one-of-a-kind item. Serious inquiries only. Reply to Box 154 at this newspaper. 

 After seeing that Peppermint Patricia wrapper, I knew that any society that could mix two separate flavors like mint and chocolate is more open-minded than I could ever fathom. We must start this revolution so that the women of the future can feel the freedom that I felt in those brief moments. 

 It’s inevitable: Science and technology will advance beyond all imagination, forcing society to perfect itself. Imagine who you could be if you didn’t live in fear. Or more importantly, imagine the stories you could write if your life was full of adventure. 

 She turned and slapped him hard across the face. 

 But they hadn’t existed at the time of Herod the Great. And they hadn’t captured Masada until—what, 66 CE? 

 She’s thirty-six but has felt the same inside since fifteen, when she’d read a pulp magazine and knew with absolute certainty what she wanted to do with her life. 

 Nagkmur finds a chronology on the Internet and searches out a year halfway between the present and their encounter in sixth century Constantinople. The quickest way to identify when things went awry, he tells her, is to work by halves. If AD 1300 is undisturbed, the change came later; otherwise, earlier. 

 It’s not anything fatal. You know it can’t be anything fatal, because if it was, thent here would be no future self who could be sent back to warn you. 

 Fifty percent of snatchers don’t return from their first. Why? Because time is a malevolent killer that tries to eradicate us when we jaunt. But you know all that. 

 His second attempt had not been so subtle, a handgun and cartridges smuggled past Time Adventures people who didn’t even bother to check his luggage. 

 You know you’ve got the wrong equation for closed timelike curves, right? 

 “So, what exactly is a time loop?” I ask, on a wet winter’s night, as I take my shoes off and recline on the professor’s sofa. 

 I told him I was going to be a king in Medieval Times, and here I am getting rich. 

 You warned us you'd be difficult.