Disclaimer: I own nothing. If anyone is interested, I just posted a new chapter of Sweet Child of Mine dealing with Rose's first day of boarding school.
As it turned out, Castiel was amazing at research. He knew the contents of most of even Bobby's more obscure books, and he never needed a translator. It did not matter if it was written in Greek, Japanese, Latin, Hindu, Gaelic, or languages even older. He also did not need sleep or food. He never took off his trench coat, but, in the few minutes he took between books, he would smooth out Rose's note and reread it.
Dean caught him at it when he went down to the storm cellar/demon-proof panic room to get a Mandarin English Dictionary. (Usually, Dean left the studying to the geeks in the family, but with Rose in danger he could not just sit on his hands). "We'll get her back, Cas. We'll figure something out." We have to.
The angel carefully refolded the note and put it back in his pocket. He said nothing, but Dean could see the hopelessness in his eyes.
"Dean!" Sam could be heard thundering down the stairs. "Cas! Bobby thinks he's on to something."
Needless to say, Castiel was the first to reach Bobby's side, but Dean and Sam were close behind. The older man's heart broke just a little more at their hopeful faces. He did not know how much more he could lose. "I don't know how much this helps, but…I think Rose is going after the Horsemen."
No one said anything; they just waited for him to explain.
Bobby pointed to stack of newspaper articles piled haphazardly on his battered mahogany desk. "In the past two weeks, Carver Iowa has been the epicenter of some strange disease. Spokesperson said that it was a particularly nasty, mutant strain of flu, but according to the interoffice emails that Sam hacked for me, the CDC had no idea what the hell it was."
"What it 'was'?" Dean leaned across the desk to get a better look at the articles.
"Yesterday," Bobby continued, pushing the papers closer to Dean with one hand, "Everyone who hadn't already gotten killed off by this plague, suddenly got better. People are calling it a miracle."
No one bothered to see if Bobby agreed with that assessment. No one in the room believed in miracles anymore.
"Now, hallucinations were a symptom, but a couple of patients claimed to have seen a doctor turn into something nasty when confronted. His body grew snakelike, but he waved a horrible jagged scalpel in each of his six arms. His face grew," he glanced down at the notebook in his lap, "into that of a snake, complete with a forked tongue and ruby-red eyes."
"Pestilence," Castiel said with certainty in the pause Bobby took to breathe. "He was just as gruesome the first time around."
Bobby nodded, glad for the confirmation. "These same patients also claimed that the person who confronted Dr. No was a pretty girl, with baggy clothes and green eyes, who reacted to the change in the doctor by growing wings made out of light."
Sam and Dean both looked shell-shocked, but Cas' reaction was odd. It almost looked like he had the answer to a puzzle.
"She carried a flaming sword," Bobby continued, "and she cut one hand, just one, off of the monster. The body was consumed with white fire, but the hand she took with her."
"Why is she going after the Horsemen?" Sam asked, wiping his sweaty palms on the back of his pants.
"Practice maybe?" Dean suggested.
"She needs the rings," Cas corrected. "The Horsemen's Rings." He smiled. "That's very clever, Michael."
"Why is that clever?" Sam asked, frowning.
"Dean was right, she does need training and this provides good training. But also…" He pulled a book out of Bobby's shelves and flipped it open to the exact page he needed. It was written in a language that none of the humans, not even Bobby, understood. But on the reverse page was an illustration depicting a whirl of black and red below a small image of four rings intertwined. "The four rings together can open Lucifer's Cage. It is a contingency plan. If she cannot outright defeat Lucifer in the field, then perhaps she can distract him enough to allow Michael to shove him into the pit. Lock him away again."
"That's not really any safer is it?" Dean was not really looking for an answer, but he wished he did not know it.
"No," Castiel said, his hand sneaking into his pocket again, fingers softly tracing the folds of the paper.
"So, what do we do?" Sam asked, looking around the room, the absence of a fifth person hitting him in the gut for the ninth time that hour.
"There are still two Horsemen," Dean said decisively. "She's going to hunt them down. Least we can do is help her out."
Everyone was quiet for a moment until Sam squared his shoulders and asked, "How do we find them?"
Castiel pulled out his note and studied it for a moment. "I am sorry, Love." He went over and, with an air of finality, shut it in Bobby's desk drawer. "I can help with that."
He gathered together some supplies from Bobby's kitchen - myrrh, rosemary, aconite, and devil's shoestring - and put it all in a silver bowl. He then took a copper knife from behind Bobby's tv cabinet, and carved an elaborate symbol onto his arm. He did not even flinch.
He angled his arm over the bowl and let the blood flow freely for a moment before tossing in a lit match. The mixture burned with a supernatural brightness. He held the bowl aloft and spoke a few words in another language that no one else understood, but it reverberated around the room like thunder. He did not yell, but the windows shook and books fell from the shelves. He breathed in the smoke and his body contorted, back bending in a way that should have broken it. He dropped the bowl, spilling the contents all over the floor and let out a muffled cry of pain as the symbol on his arm blazed red.
Just like that, it was all over. Castiel was still breathing heavily, lips showing evidence of blood, when he looked down at his arm. The symbol had formed into a scar that not even his powers could heal. "Los Angeles. They're in Los Angeles."