I should warn you, there will be a little bit of violence and death later. If you don't want to read that, please don't go further. I don't own the Big Bang Theory or it's characters.
What if Sheldon came back from a trip, and not only was Penny no longer there, but only he remembered the exuberant blonde who lived across the hall? Where had she gone? Had she been a figment of his imagination? Is that why she never had a last name? Can he trust his memories, or has he finally went over the edge?
Sheldon was not happy. He had just come back from a weekend lecture and Leonard was supposed to pick him up at the train. After 30 minutes, he had called Leonard but gotten no answer. A strike worthy offense to say the least. Then he had called Penny, but her phone was shut off. Really, that woman has no idea how to manage her money, he thought in exasperation. So, he had to take a cab. It had been horrible. The driver kept trying to look at him and talk, instead of watching the road.
He glared at Penny's door as he unlocked his. He would have to go over after he had unpacked and showered to let her know he was home again. Sheldon wheeled his luggage back to his bedroom and froze. Someone had been in his room. He caught the faint scent of vanilla and scowled. Penny! She knows no one is allowed in his room. What possible reason could she have for breaking his rules?
He quickly unpacked and then went to shower away the germs from the cab. It wasn't until he was dressing that he noticed something unusual. His Flash shirt was different. It looked like his shirt. It was folded precisely. But it wasn't his. He considered the possibilities. The only logical conclusion was that someone had replaced his with a new one. He narrowed his eyes. Could that be the reason for Penny's invasion? Had she somehow ruined his and thought he would not notice the replacement? He grabbed the offensive shirt and stormed across to her apartment.
Knock knock knock Penny.
Knock knock knock Penny.
Knock knock knock Penny!
After a minute, he knocked again. He glared at her door. She must be at work. Well, no problem. He would call her there. He was not postponing his wrath at her careless disregard for his personal property simply because she was not present! She had absolutely no appreciation for privacy! He went back into 4A and grabbed his phone. After dialing he sat in his spot and waited for someone to pick up.
"Cheesecake Factory, how can I help you?"
"Yes, I would like to speak to Penny, please. She's a waitress."
"Sorry, buddy. There's no waitress named Penny here."
Sheldon frowned I confusion. "But of course there is. Penny. Blonde, loud, large Nebraskan man-hands."
"Um, yeah, sorry dude. Doesn't sound familiar. Besides, I've been here 2 years and I know all the staff. None of them are named Penny."
Sheldon stared at the phone. Obviously that guy was an idiot. How could he not know Penny if he has worked there for 2 years. An answer popped into his head immediately. Penny must have known he would be upset and had asked this guy to tell anyone who called for her she wasn't there. He narrowed his eyes. She was a devious adversary, but he would not be thwarted.
Unfortunately for Sheldon things just got weirder from there.
He could hear two people in the hall, signaling Leonard and Penny were home. He stayed in his seat waiting to see which one would apologize first. Leonard came in alone and apologized profusely for forgetting Sheldon, he explained about getting caught up in an experiment, and losing track of time. Sheldon glared at him through the entire story.
"You have earned a strike for this Leonard. Your redundant experiments are no excuse for forgetting me. If I wasn't so upset with Penny, I would berate you more."
Leonard looked at him strangely. "Who's Penny?"
Sheldon rolled his eyes. "It is useless to try and protect her, Leonard. I know about the shirt. She cannot hide forever."
Leonard looked confused. "Okaaaay. First of all, why would I protect someone I don't know, and second, what shirt?"
Sheldon sighed. "My orange Flash shirt, Leonard. The one that was replaced. It wasn't too hard to detect. Are you implying you had no knowledge of the switch?"
Leonard sat down on his chair. "Sheldon, are you feeling okay? Because you aren't making any sense. I don't know any one named Penny. I have no idea what you are talking about."
"Not funny Leonard. Penny, our neighbor, has been in my room and switched my Flash shirt for a new one."
Leonard looked really worried now. "Sheldon, our neighbor is Amy Farrah Fowler. She's lived across the hall from us for 5 years. She's your girlfriend. You've been dating, or rather…well, whatever you call it, for two years now."
Leonard stood up and walked out into the hall. Sheldon followed him. A quick knock and Amy opened the door. Sheldon's eyes bugged out. The living room was completely different. Gone was the teal sofa, the green chair, the mess. Instead he saw Amy's furniture. Her tan couch with the blanket over the back. Her harp near the bedroom door. Her shelves filled with books on neurobiology.
He turned to Amy and frowned. "Where are Penny's things and why are you in her apartment?"
Amy looked at him in bewilderment. "What is he talking about," she asked Leonard.
Leonard looked at Sheldon and then back at Amy. "I'm not sure. He keeps saying someone named Penny lives here and she stole his shirt."
Amy frowned at Sheldon. "Have you sustained a head injury, unusually high temperature or been partaking in recreational drug use?"
Sheldon scoffed loudly. "Of course not. I am fine. You two are the deranged ones! I want to know where Penny is. She is your best friend, so surely you know."
Amy shook her head slowly. "No. My bestie is Bernadette. I don't know anyone named Penny." Sheldon pushed inside and stalked to the bedroom. No Care bears. No messy floor. No vanilla scent. Sheldon looked back and Amy and Leonard and slowly sank to the floor. How could this be?