"Oh, look at you," the Doctor said, eyeing Clara in the doorway. "Lovely little dress you've got there."
"…Thanks?" Clara replied uncertainly, watching the Doctor drink in her appearance. He had never acted like this before. Suddenly self-conscious, she tugged the hem of her forest-green dress down to her knees. Something was…off about the Doctor. They were investigating an abandoned home in Heron Creek, Iowa, and Clara had just gone to see who had been pulling up the drive when she heard a loud bang come from upstairs, where the Doctor had been scanning the master bedroom with his beloved sonic. Remembering the last time one of them had been involved with an unexplained bang (the sonic screwdriver had rolled from the TARDIS console onto the floor and Clara had slipped on it, nearly sending the space-and-time ship careening into a meteor when she'd grabbed the controls; as a result, the sonic hardly left his hand anymore), she dismissed the loud engine rumble as an echo from the nearby highway and had dashed upstairs to check on the Doctor, where she found him standing in the middle of the room with an almost-sinister smirk on his face. "Did you find anything?"
"No, I think she found me," the Doctor said, striding closer to Clara. His eyes flicked down to her chest (completely covered, thankfully) for a second, and Clara took the initiative to back up a few paces. She was getting seriously uncomfortable—what was wrong with the Doctor? What had happened for those few seconds when she had popped downstairs?
The Doctor reached a hand out to her face, but she swiped it away with a strike so fast her own eyes couldn't see it. "What are you playing at, Doctor?" she said, half-accusingly. She heard the sound of a loud car engine in the drive, pulling up to the house and then abruptly cutting off. "Someone's here, I'll just go tell them some story," she said, suddenly desperate for any excuse to get away from the Doctor. "If we don't know what's in here, it'd be better to head them off—"
As she turned on her heel, one of the Doctor's hands shot out to her elbow and pulled her back around aggressively—an incredible departure from when he'd gently hold her arm to prevent her from touching the wrong knob or lever on the TARDIS. Clara was about to order him to let her go (even though slapping him sounded far more satisfying at this point) when she caught sight of the sonic screwdriver lying on the floor.
After the almost-meteor-crash, he would never treat it so carelessly.
Something was wrong with the Doctor.
The Doctor (if it was really him) saw her staring incredulously at the screwdriver lying on the floor, and knew she was beginning to solve the puzzle. Clara, seeing him watching her, hastily rearranged her features into defiance to throw him off, but she was a second too late—he had seen, and he now knew.
Abandoning diplomacy, she dug the fingernails of her free hand into the back of the Doctor's, causing him to yelp and let go of her, backing a few paces away from her sharp-as-claws nails. She thought about kicking him below the belt, but she decided that it would be better to follow the Doctor's first instruction on every new adventure: run.
Unfortunately, she didn't get very far.
As she turned away, she felt a great, whooshing, invisible force envelop her and pull her up and backwards through the doorway, slamming her against the opposite wall. Her head was throbbing from hitting the plaster, and she had the peculiar sensation of being wrapped in a heavy quilt, but the most concerning thing was the fact that the Doctor was standing just to the right of the doorway, holding a hand out as if controlling her movements.
In some oddly-distant part of her mind, she thought, what the hell can't a Time Lord do?
"Doctor?" she called uncertainly as his lanky form slowly drew closer to her like a cat to a mouse. "Care to explain?"
The Doctor was now just feet from her. In that distant part of her mind, she was proud that now, at least, she was significantly taller than he for once, being suspended in midair two feet off the ground. He looked up at her with a perverse amusement, blinking—and when he blinked, his eyes-the pupils, irises, whites, everything- turned completely black.
Clara was terrified. Her mouth was opening to scream, but the Doctor's hand, held flat, suddenly clenched into a fist, and Clara felt her own throat tightening as he cut off her voice. The Doctor's hand dropped as he meandered closer, mockingly lifting a finger to his lips and shushing her. "I don't think you want to try that again," he threatened as he lowered his finger, blinking so his black-as-tar eyes returned to normal.
Somewhere in the corridor, a floorboard creaked. The Doctor (or whatever the hell he was) swiveled around to face the doorway, when suddenly two men appeared at its sides, holding…water pistols? What on Earth would a water pistol do? The shorter man pulled the trigger, sending a fine stream flying toward the Doctor. When the water hit the Time Lord, he started steaming and crying out in pain.
Clara, now beyond horrified, screamed, and although no sound came out, it was enough to attract the attention of the taller man. "Just stay calm, please, Ma'am," he said, keeping his neon yellow pistol pointed at the Doctor. "We'll get you down as soon as possible."
The Doctor, angrily shaking off the apparently-acidic water, threatened, "I'd like to see you try. You think a little holy water is enough to take me down?"
As the two unknown men threatened the Doctor, there was another whoosh, but this sounded less like the wind and more like a bird taking flight. Suddenly, a third newcomer appeared right out of thin air in front of Clara (who hardly even cared about the gaping absence of logic in this situation anymore; she just wanted her Doctor back). Clara could tell he was a man from the set of his shoulders and his short hair, but his long trench coat hid anything else. Thankfully, whatever spell that had been cast upon Clara's vocal chords remained effective—if her shout of surprise had been audible, she would have given away this trench coated man's appearance, and something in the demeanor of the other two newcomers told her that they didn't want the Doctor to turn around.
Suddenly, the shorter of the first two intruders said, "Maybe holy water won't help, but an angel sure will."
Trench Coat's hand shot out to the Doctor's elbow and pulled him around roughly, like the Doctor had done before to Clara. As the Doctor's face turned to him, Trench Coat firmly placed the heel of his free hand to the Doctor's forehead, and roughly forced the Doctor to his knees. There was an expression of pure agony on the Doctor's face—apparently, whatever Trench Coat was doing to him caused him great pain. Suddenly, the enchantment upon Clara ended, and she fell to the ground; the resulting groan told her she had her voice back. A second after Clara regained her footing, black smoke flooded out of the Doctor's mouth, accompanied by the Doctor shouting painfully. His eyes had turned that soulless black again as the smoke, like some kind of ethereal worm, poured from his mouth, streamed to the window and zoomed away. Clara stumbled over to Trench Coat and tried to pull him off the Doctor, but the taller of the two men Clara had mentally nicknamed the Plaid Twins grabbed her arm and pulled her away from the struggling pair. She tried to fight her way out of his grasp (and even debated pulling his long hair) but before she could break free, the stream of roiling smoke that had infested the Doctor abruptly ended, the tail end of it following the rest zooming out the window. The Doctor's eyes reverted from the horrifying black to his normal green and closed, and he slumped backward in Trench Coat's arms, unconscious.
"The demon has been purged," Trench Coat said in an unexpectedly deep voice. The taller Plaid Twin's grip on Clara suddenly loosened, and she wrested her arm out of his grasp, falling to her knees beside the Doctor. "He must rest now. He will awaken in a few hours."
"Awaken?" the shorter Plaid Twin said, lowering his water pistol. "I thought that if an angel exorcises a demon, both the demon and the host die."
"Human hosts do. He is not human," Trench Coat replied as Clara pulled the Doctor from his arms and gently laid him on the ground. She smoothed back his hair and lightly slapped his cheek, trying to wake him up.
"Not human?" the taller Plaid Twin said. The shorter one reached behind him and pulled out a shotgun, pointing it at the Doctor's limp body.
"Not human," Trench Coat clarified.
Clara usually had a high threshold for nonsense that came from traveling with the Doctor, but she couldn't stand the stuff today. She lunged for the sonic screwdriver, wrapped her hand around it, and brandished it in front of her like a weapon, flying to her feet.
"Okay, listen up: you're going to tell me who you are, what happened to the Doctor, and what you did to him," she said commandingly.
The Plaid Twins were both brandishing guns- real, proper guns- now. "Just put the glow stick down and we'll talk, toots," the shorter one said.
"Put your guns down first," Clara retorted, gesturing at them with the sonic screwdriver. "And don't call me 'toots'."
The Plaid Twins exchanged a glance, and then the taller one lowered his gun. The shorter one, and then Clara, followed suit. "Can you tell us who you are, and who he is?" the tall one asked.
"Tell me your names first," Clara said, deciding that extracting information from the men bit by bit would be the better strategy. By the looks of it, they were used to dealing with mayhem. Good thing she was, too.
"I'm Sam Winchester," the taller Plaid Twin said. He gestured to the shorter Twin and said, "This is my brother, Dean."
Maybe plaid runs in the family, Clara thought. "Who's he?" she asked, nodding toward Trench Coat.
"My name is Castiel," Trench Coat said, moving from the side of the room over to the Winchesters. "I'm an angel of the Lord."
Clara blinked.
"Who are you and what's your boy toy?" Dean demanded. Clara could tell he was the most suspicious of the trio.
Slightly offended, Clara replied, "My name is Clara Oswald. That's the Doctor."
"That's the Doctor?" Dean said doubtfully. "Look, sweet cheeks, you may be pretty, but you certainly don't have a brain. We've met the Doctor before—that's not him."
"Unless I'm very much mistaken," Sam said, gently pressing two fingers over the Doctor's jugular vein, "I'm pretty sure this is the Doctor, Dean."
Dean looked from the Doctor's languid body to his brother's raised eyebrows disbelievingly. "Come on, Sam," he said. "We met the Doctor, remember? We were hunting that Jinn in Elmwood, and the Doctor trapped it in the bathroom? The real Doctor, not this weirdo with a bowtie. Remember, he had that beautiful leather jacket and a different sonic screwdriver. Yeah, sweetheart," Dean directed this statement at Clara's shock, "I know a sonic screwdriver when I see one."
"Dean, he's got a different pulse," Sam appealed. "Remember when he said he had two hearts? Well, his pulse is going—" Sam tapped a rapid series of four beats on the rotting floorboards. "That's two heartbeats, Dean. This man has two hearts. He's gotta be the Doctor."
"Well, he's an alien," Dean said, "Who knows how many aliens have two hearts?"
"The TARDIS!" Clara exclaimed. She hadn't understood quite all of the conversation (especially about the Doctor wearing the leather jacket) but apparently, the Doctor and the Winchesters knew each other, and she had to make them realize. "You've met the Doctor before, right? Well, if you have, you've probably seen the TARDIS."
Dean nodded, unsure of where the conversation was going.
"Here," Clara said, "If you look out the window at the end of the hall, you can see the TARDIS in the backyard. And if you really have met the Doctor before, you'll know it's the only TARDIS left in the universe."
Dean peered at her suspiciously and then went to the window. She could see by the contracting that his eyebrows that he was surprised to see the TARDIS there—actual proof that she was telling the truth. "So that's the Doctor," he said, surprised. "How did he go from Captain 'Fantastic' to this bowtie-wearing clown?"
Sam gave a nearly imperceptible shudder.
"Can we please help the Doctor?" Clara asked desperately. "Just find him a place to lie down?"
"Good idea," Sam agreed. "Dean—get his legs." Together, the brothers carried the Doctor down the hall to a moldy bedroom, furnished with a rusty iron bedspring, bare mattress, and partially rotted wooden nightstand. Clara and Castiel followed, the former worriedly and the latter indifferently. Clara bustled over the Doctor, rearranging his body and clothing into a more comfortable position. She even went so far as to demand Castiel to shed his coat so she could drape it over the Doctor. She cared greatly for her friend—after all, he was the one who had shown her the stars. Hell, the children she looked after even thought he was her boyfriend. Some weird things had happened today, including the Doctor being possessed by a demon, which wasn't even supposed to exist. If the Doctor was possessed by something so obviously not good, then that meant that the Doctor didn't know what he was doing. And that scared Clara to death.
Once she was sure the Doctor was comfortable, with Castiel's coat draped over him like a blanket and Sam's rolled beneath his head like a pillow, Clara turned to the three men, of which only Sam had helped her get the Doctor comfy.
"Explain," she commanded simply.