I was carrying a pair of grocery bags in from the garage when I saw him.
“Sorry Doctor,” he said while pointing what looked like a gun made out of glass at me. “I can’t let this happen.” He squeezed the grip.
I sighed and stepped around him and into the kitchen, putting the bags on the counter. He looked at the gun then pointed and squeezed it at me again. More nothing happened. He yelled in frustration and threw the gun at me. He missed and the gun bounced off the side of the refrigerator.
“Watch it!” I said, getting annoyed. “You could break something.”
He yelled again and started to rush at me but tripped. He hit the ground hard and lay there unmoving. I sighed again and started putting the groceries away.
Some minutes later I was looking in the back of the refrigerator to see if I had any beer left when I heard him groan. I turned around in time to see him push himself up into a sitting position. He looked around and saw me as he staggered to his feet.
“How?” he asked finally. “What did you do?”
“Nothing.” I said, popping the tab on the beer. “No need to. I figured that out a while back.”
He paused. “What do you mean?”
I leaned back against the counter. “Who do you think I am?”
That seemed to startle him. “You’re Henry Armstrong, right? The physicist?”
I shook my head. “People keep telling me that, but physics isn’t my thing.” I took a drink. “Neither is time travel.”
He took a couple of steps towards me. “So you *are* him!”
I shrugged. “So people keep telling me. But I’m not a physicist. I’m the assistant manager at the Food World.”
He paused. “People? Who? What are you talking about?”
I took another drink. “Do you think you’re the first person to have this idea? Well, you aren’t. A lot of people seem to think I invented time travel. Or will invent it. Or something. And apparently I will at some time because my doing so seems to have made a lot of people angry enough to come back and try to kill me before I invent it. A couple of you show up every week these days.”
His eyes narrowed, looking first at me then at the gun, still lying on the counter where it had landed. “Oh, so someone brought you a nullifier? That’s what it is.”
He started to move towards me again but I held up a hand. “Nothing that complicated. It’s actually quite simple when you hear the explanation. And believe me, I’ve heard it dozens of times. Now, why are you trying to kill me?”
He clenched his fists. “You invented time travel! Do you…”
I cut him off. “OK, let’s say I will. Now, how did you get here to try to kill me?”
“I used the time machine at…”
I cut him off again. I had had this conversation many times. “OK, put it together. I invent time travel. You use time travel to come back to now to kill me before I can invent it. So time travel doesn’t exist. So you can’t come back to kill me. So I invent time travel. You can’t kill me because the means you use to kill me require that you not kill me. Get it?”
He shook his head. “Some people have made changes.”
I shrugged. “Not many, and never for anything important. Or so I’ve been told. People like you have been showing up my entire life. All of you keep trying to kill me and none of you succeed. Nothing ever works. It’s kind of annoying, really.”
He looked from me to the gun again. “So… you can’t be killed?”
“Apparently.” I said.
He thought a bit. “Wait… You said you were just a grocery store manager?”
“Assistant manager,” I corrected him. “Why not? Apparently I’m going to invent time travel some day whether I want to or not, so I haven’t been particularly motivated.”
“But you’ve been studying? Working on it?”
“Nope. Again, why bother? Apparently I can’t not invent it. It will happen at the proper time.”
He shook his head. “So… you aren’t in control of your own life then?”
I finished the beer and nodded. “Yeah. That’s the downside. Just like you can’t kill me, I apparently can’t do anything different either. So why try? I…”
We were interrupted by a popping sound and a brief flash. Another person appeared in the room, wearing a jumpsuit and helmet and holding a ball-like object in his hand.
Another sigh. “Hi.” I said. “Welcome to…” There was a bright flare from the ball.
Henry Armstrong’s head exploded outwards, splattering the kitchen with gore. The beer can dropped to the floor as the body wobbled, then fell itself. The first visitor looked at it in surprise then turned to the newcomer.
“You know, he had just convinced me that he couldn’t be killed. Guess he was wrong.”
“He couldn’t.” said the newcomer, checking something on the ball. “Not by you anyway.”
The first visitor looked at him. “What do you mean?”
The newcomer shrugged. “The universe will prevent a paradox at all costs. We figured that out as soon as time travel was proven to exist. But there are exceptions.”
The visitor nodded. “Yeah, some people have changed things, but not many.”
The newcomer smiled under his visor. “Actually, it’s easy to change things. As long as the result is the same you can change the details all you like. That’s the loophole. In order for there to be a paradox someone has to realize there is one.”
“OK, yeah, but…” he pointed at Armstrong’s body, “how did you kill the creator of time travel then? Wait… If you killed the creator of time travel, how are we still here?”
“Him?” The newcomer gestured at Armstrong. “That guy never did anything. He thought he was destined for fame and just coasted along, expecting it to happen without any effort. He doesn’t invent time travel.”
“Then who does?”
The first time traveller hesitated for a moment then his eyes widened. He dove and grabbed for the gun still on the counter. The ball flared.
The newcomer knelt over the other traveller’s body and placed the gun back in its hand. He then searched briefly before finding the recall unit on his arm. He pushed the button and stepped back, watching until the body vanished with a pop and a flash of light. He then removed the recall unit from his own wrist and wrapped it around the arm of Armstrong’s body. Another pop and flash and the newcomer was alone in the kitchen.
He sighed and looked around. He would have to clean up the mess but that could wait. Removing his helmet, he opened the refrigerator and found another beer then found and dialed the phone. He waited.
“Hello, University? Yes, this is Henry Armstrong. I’ve decided I need to go back and get my degree and am wanting to know your enrollment procedures.” He paused, listening.
“Well, I’ve always been interested in physics…”