Genre: SuperWho (Doctor, Sam, Dean, Castiel, OC)
Slash: None (yet)
Part: 1 out of I don't know - at least over 5… maybe close to 20…

The Winchesters knew Cas was the best choice to go in undercover. He hadn't been hunting with them long, but it was a hospital the boys had been admitted to before and they didn't want to risk being recognized.

"Okay, Cas," Dean wanted to make sure he understood the plan, "Remember to call us as soon as you find him. If he's in there at all."

"Of course, Dean." Cas was contemplating how humans react to being sick. He was just admitting himself for chest pains, something they were sure he'd at least be kept overnight for. However, since he'd never experience the particulars of that condition, he settled on the assumption that it was similar to how it feels when an angel is warded away.

"We don't know if this guy is dangerous or not," Sam reminded him, "So don't do anything without us. Just scouting it out."

"I understand," Castiel nodded and placed a hand on one should of each brother, shaking them gently to reassure them, "Don't worry about a thing." There was a grin on his face, Dean recognized it as the same smile Cas had when he first told them that he wanted to be a hunter. He still wasn't sure how to react to it at this point.

Dean cleared his throat as Cas started walking towards the hospital. The three of them had a lead that the Brit was inside, but they didn't know why.

Yesterday they had seen him waving a small, glowing object (that was making quite a noise) while running down the street towards some lady. They had followed him, staying hidden around a corner on the sidewalk as the man followed her through an alley and behind a building. As the man turned round the corner to walk back down the alley, he was covered in a green ooze and the woman was calmly walking beside him.

The two brothers quickly attempted to act casually, staring into a window of a shop alongside the street. Castiel hadn't picked up on the plan immediately and Sam had to quickly pull him over to play pretend as well.

When the man reached the sidewalk, Castiel turned to him, "What is that you're covered in?" he was blunt and forceful with his words.

"Oh, this?" The man gestured to himself and glanced at the woman, "This is a… snot. Yeah, see, my… um… sister here has a very nasty cold and she didn't want to sneeze in public so she ran down the alleyway behind the building. I was trying to catch up to her and startled her when I turned the corner."

The brothers looked at each other, still standing in front of the window pretending to not listen. Castiel tilted his head, "That is an awful lot of mucus…"

"Yes, well, that is why I am heading… a, home. House, well, a flat really," he lifted his chin up and stared off the side, not looking at anything particularly, "I mean I guess I'd typically be renting the place if I had a landlord , but it's pretty big too…" he trailed off into his own thoughts, but soon realized Castiel was still staring at him, "So! I will be heading off, sorry to worry you, come along, sister!" He grabbed the woman's hand and walked past Castiel and the brothers. After walking halfway down the block, the two of them started running.

So now here they were, at the hospital. Someone at a local restaurant talked about a strange Brit being admitted (the boys had said their cousin was in town from England and was lost). They could only hope it was the same one. They knew he wasn't telling them the whole story, and with there being five recent murders and a mission person in the past two days, they knew he had something to do with it. But why had he also checked himself into the hospital?

Castiel disappeared through the hospital doors. Now all Sam and Dean could do was wait for him to call. They decided to get breakfast.

—-

Cas was standing in the emergency room lobby.

"Can I help you?" A lady ask him. She was wearing teal scrubs behind a counter surrounded by glass walls. Lots of folders and files were on shelves behind her and the area was large enough to have several other men and women looking at them, answering phones, and doing normal human activities.

"Sir?" She asked again.

Castiel realized that he hadn't started playing sick yet. He grabbed his chest with his left hand and leaned into the counter with his right, "Oh, yes," he scrunched his face and spoke through his teeth as he hunched over, "I'm experiencing excessive pain in my chest area. It's… crushing." He recalled how he felt when warded away and started breathing heavily as if his lungs were tightening up.

"Oh, oh goodness, okay. Is anyone with you?"

He took a second to answer, "No, no one is with me. I'm - I'm travelling on business."

"Ok, sir, let's get you into an exam room."

Castiel was taken through several procedures until he was finally put in a bed and hooked up to a heart rate monitor. All of the tests came back normal, but Cas insisted that he stay overnight. He continued every-so-often to pretend like a pain shot through his chest. As luck would have it, the British man was in a room adjacent to his and Cas could see him from where he was in bed. He had also passed it on the way to his own room and heard the man introducing himself to one of the nurses.

"Excuse me, nurse!" Cas called to man in the hallway, "Sorry, I'd like to use the phone, how - how do I…"

"Here," the young man pulled a phone closer to the bedside, "Dial 9 and then the number you want to call. Press this button if you need anything."

Cas had admitted himself early that morning, it was about four in the afternoon now. He called Dean's cellphone number.

"Dean. He's here. He's calling himself John Smith. I suggest you get here as soon as possible."

"Yeah, okay. We're on our way."

They hung up and in about an hour the two boys were sitting next to Cas's bed, trying to avoid being seen by the other man.

"Have you seen him do anything?" Sam asked, using a lot of willpower in order to not turn around and look for himself.

"No, he's just been in his bed."

"No phone calls or visitors?" Dean added.

"No, he -"

"What about any mumbling or weird eating habits?"

"Boys!" Cas raised his voice slightly and sat himself up. He looked down and then out the window, "I told you all I know. If there had been anything else I would have -"

"Sorry to interrupt," the Brit stood in the doorway, "You lot look like the ones from the other day! Fancy meeting you here!" He beamed a wide grin at them.

Dean stood up defensively, "Did you get sick from being covered in mucus?" He asked cynically, "Or maybe you'd like to tell us who you really are."

The man's chin dropped and he looked at the others from beneath his brow, "I'm a friend, if that's what you mean."

Castiel disconnected himself from the machines and stood up from the bed, walked over to him, and placed his hand on the Brit's forehead. The man flinched slightly, like Cas had shocked him. The angel pulled away.

"He's neither demon nor angel." Cas said as he let down his hand and turned to Sam and Dean, then back to the man in the doorway, "but you certainly aren't human."

"Angel, then, you?" the man tilted his head toward Castiel. Cas simply nodded. The new guy looked at Sam and Dean and said, "I think it's best we talk privately," almost in a whisper. He then started walking down the hallway.