Hoping to alter the events of the past, a 19th century inventor instead travels 800,000 years into the future, where he finds humankind divided into two warring races.

Über-Morlock: We all have our time machines, don't we. Those that take us back are memories... And those that carry us forward, are dreams.
Über-Morlock: You built your time machine because of Emma's death. If she had lived, it would never have existed. So how could you use your machine to go back in time and save her? You are the inescapable result of your tragedy, just as I am the inescapable result of you. You have your answer. Now go.
Filby: Which three books would you have taken?
George: What have you done? Thousands of years of building and rebuilding, creating and recreating so you can let it crumble to dust. A million years of sensitive men dying for their dreams... FOR WHAT? So you can swim and dance and play.
[last lines]
Mrs. Watchett: Mister Filby, do you think he'll ever return?
Filby: One cannot choose but wonder. You see, he has all the time in the world.
George: When I speak of time, I'm speaking of the fourth dimension.
Über-Morlock: Who are you to question 800,000 years... of evolution?
Alexander Hartdegen: This is, this is a perversion of every natural law.
Über-Morlock: [grabs him by the throat] And what is time travel but your pathetic attempted to try to control the world around you? Your futile effort to have a question answered? You think I don't know you, Alexander? I can look inside your memories, your nightmares, your dreams. You're a man haunted by those two most terrible words: What if?
David Philby: Nothing can change what happened.
Alexander Hartdegen: No, you're wrong. Because I will change it.
Filby: He's got all the time in the world.
Vox: Can you even imagine what it's like to remember everything? I remember this six-year-old girl who asked me about dinosaurs 800,000 years ago. I remember the last book I recommended: Look Homeward, Angel by Thomas Wolfe. And yes, I even remember you. "Time travel, practical application."
Alexander Hartdegen: My question is why can't one change the past?
Vox: Because one cannot travel into the past.
Talking Rings: My name is of no consequence. The important thing you should know, is that I am the last who remembers how each of us, man and woman made his own decision. Some chose to take refuge in the great caverns, and find a new way of life far below the earth's surface. The rest of us decided to take our chances in the sunlight. Small as those chances might be.
Alexander Hartdegen: How did this happen?
Soldier #1: The moon. Come on, move it.
Alexander Hartdegen: That's impossible. What happened?
Soldier #1: What, you been living under a rock?
Alexander Hartdegen: Yes, I've been living under a rock! Now tell me...
Soldier #1: The demolitions for the lunar colony screwed up the orbit, okay? The moon's breaking up, all right? Now, come on.
Teacher: If you do that again, I will re-sequence your DNA.
Talking Rings: The war between the east and west which is now in it's three hundred and twenty-sixth year, has at last come to an end. There is nothing left to fight with, and few of us left to fight. The atmosphere has become so polluted with deadly germs, that it can no longer be breathed. There is no place on this planet that is immune. The last surviving factory for the manufacturing of oxygen has been destroyed. Stockpiles are rapidly diminishing. And when they are gone, we must die.
Alexander Hartdegen: You're forgetting one thing. What if?
George: David, I've got to tell it now. While I still remember it!
Filby: Relax, try to relax. You've all the time in the world.
George: You're right David, that's exactly what I have. All the time in the world.
Filby: If that machine can do what you say it can do, destroy it, George! Destroy it before it destroys you!
Filby: Take your journey on your contraption. What would you become? A Greek, a Roman, one of the pharaohs?
Vox: [an image of Vox appears] Welcome. How may I help you?
Vox: [Alexander Hartdegen looks behind Vox] Over here.
Alexander Hartdegen: I could come back a thousand times... and see her die a thousand ways.
Alexander Hartdegen: You were right, Philby. We did go too far.
David Philby: [looking at a futuristic picture] I wonder if we'll ever go too far.
Alexander Hartdegen: With what?
David Philby: [pointing at the picture] With this. With all of this.
Alexander Hartdegen: No such thing.
Mara: Some things are better left unsaid.
Jogger: Hey.
Alexander Hartdegen: Hello.
Jogger: Nice suit. Very retro.
Alexander Hartdegen: Thank you.
Jogger: Bet that makes a hell of a cappuccino. That thing.
Mara: Why have you come here? Why have you traveled through time?
Alexander Hartdegen: To have a question answered.
Mara: A question?
Alexander Hartdegen: Yes. Why can't I change the past?
Mara: Why would you want to?
[a look of realization]
Mara: You've lost someone. Someone you loved very much.
David Philby: A professor from Columbia University should not be corresponding with a crazy German book keeper.
Alexander Hartdegen: He's a patent clerk, not a book keeper, and I think Mister Einstein needs all the support I can give him.
Talking Rings: My name is of no consequence.
Über-Morlock: Come a little closer, I don't bite.
David Philby: I'm glad he's gone. Maybe he's finally found a place where he can be happy.