• Ryan Wheeler walked particularly fast that evening. His briefcase swings broadly by his side as his arms pump and he travels down the dirty street. He was later than usual; his boss had asked him to stay in the office, and he wanted a promotion badly. He had worked overtime before, but now that it was November, and the days were shorter, it was already dark outside. In that part of town, no one left their house past nine o' clock, especially not carrying anything valuable.

    He turned a tight corner, as the space between the buildings was becoming very narrow, only to find that all the lights had been extinguished. He was only about 30 yards from his apartment. If he just ran through it, he'd be there in a matter of seconds.

    A trash can clattered from somewhere in front of Ryan, but it was too dark to see. "Who's there?" Ryan muttered automatically, voice trembling.

    "Are you Ryan?" He had been scared already, but the fact that this stranger knew his name made it all the more terrifying. "Well?" The man was angry.

    "Yes! Yes, I'm Ryan. What do you want? I have money. You can have it." The man in the shadows laughed. The sound was very familiar to Ryan, but he couldn't quite place it.

    "I hope to God I never end up like you." His chuckles subsided, and then there were a few moments of silence. With a small shuffle and a glint of metal from the shade, a figure burst from the darkness, brandishing a knife. Ryan cried out in fear, backpedaling as fast as his legs would carry him. The stranger swiped, missed, and lost his balance, falling onto his side. Ryan seized the opportunity to bring his foot down hard on the ribs and arm of his attacker, and the mugger let out a yelp.

    "Help!" Ryan shouted to the surrounding homes. "Help me!" A few lights turned on in the windows above. The attacker was getting up slowly, clutching his side, knife still gripped tightly in his left hand.

    With a jab, he aimed for Ryan's stomach. Ryan caught his wrist and twisted hard. The knife fell to the ground, and both men dived for it. Ryan swiped it a split second before his opponent, and held it to the man's neck. The man's eyes grew wide, and Ryan was overcome by a feeling of deja vu such as he had never felt before. It was as though he had seen this man every day for his entire life, but surely they had never met prior to that day. Ryan pushed him to the ground, the knife still at the ready.

    "Don't kill him! Do not kill him!" A man with a police uniform came hurtling down the alley the way that Ryan had come. "Stop! Drop the knife!"

    Ryan looked in horror at the weapon in his hand, and then looked pleadingly at the officer. "No, sir, it's not what it looks like! I didn't... he attacked... I-"

    "I know, Ryan. Just don't kill him, you'll regret it." Ryan stood speechless for the second time in ten minutes. Did everyone know his name?

    "Ryan, you're coming with me." The policeman pulled out a pair of handcuffs. Ryan stuttered incoherently, but looked toward the man on the ground and said "Him, not you."

    "What is going on here?" Ryan asked desperately. "Who are you people?"

    "Well, this man," the officer said, apprehending the other Ryan, "Is you. From the past. I'll let that soak in for a bit."

    "You're joking. This is a big joke. It has to be." The Ryan from the present ran his hands through his hair agitatedly and paced. "Are you suggesting that time travel exists?"

    "Wow, I'm still sharp ten years down the road," younger Ryan said, sounding impressed.

    "That's exactly what I'm saying, son." The officer pulled a radio from his belt and spoke in code, but both Ryans heard their name. "This man traveled ten years in the future to kill you." I'm a time-travel law enforcer. My whole job is to prevent paradoxes like this from occurring. See, if you had killed your past self, then you would simply cease to exist. It's a tricky business."

    "Even if this was all true," Ryan said, still forcing himself to believe that he was being pranked, "Wouldn't I remember all this? Wouldn't I have known that I would travel forward in time to attack myself?"

    "Well, that's what this little doohickey is for." The policeman pulled out what looked like a taser. Both Ryans eyed the device suspiciously. After a second of typing in some numbers, he whirled around to face present-day Ryan and jabbed him in the forehead. He fell to the ground, and seemed to be sleeping deeply.

    "Gotta love memory modification." Past-Ryan laughed as the police officer pulled them back in time.