Dean took another swallow or three of whiskey and set the bottle back into his bag. Sam was due back to the bunker anytime now and Dean didn't want to hear any more griping about his drinking. Or his not eating. Or his not sleeping.

He pulled the bottle out again and took another swallow and tucked it away again before turning back to his research.

"Dean?" Cas's voice suddenly in the library made him start.

"Cas? A little warning next time?"

"Forgive me; I thought that would be warning enough."

Dean grumbled a sigh and flipped open the next file folder in the pile on the table.

"What do you want, Cas? I'm a little busy here."

Cas walked over to the table and stood next to Dean.

"I wanted to talk to you about your brother."

"Oh, really? Well, I don't have a brother anymore, or haven't you heard?"

Cas looked as sour as a disappointed pickle. He took a deep breath and seemed about to launch into a tiresome lecture, but before he could get one word out, they heard the sound of Sam coming in the front door.

"It seems I'll have to use extreme measures." Cas said. He waved his hand in front of Dean. At first, nothing seemed to have happened, but when Sam came down the stairs, he slid his duffel to the floor and looked around the library.

"Hey, Cas. Is Dean around?"

So – Dean figured he was somehow invisible to Sam.

"Sam – I'm afraid I have some troubling news." Cas said.

"Where's Dean?" Sam demanded immediately, his voice low and threatening. "What happened?"

"It's the Mark of Cain. I'm afraid –" Cas sighed like he truly had bad news to deliver and Dean wondered what the hell was going on. "Cain told Dean that there would be consequences of accepting the Mark and I fear – Sam – "

"Where is he?"

"In hell."

"What?" Sam took a step back like the words were a physical blow. "Why? How? What – no, you know what? Never mind. Just take me there." He bent down to his duffel and stood up with the demon blade, angel blade and Colt. "Let's go."

"You want me to take you to hell?" Cas asked, like he was surprised.

"I know you can get there. You take me to Dean. Now."

"Sam – when you went to get Bobby, because his soul wasn't damned, you were on the outmost ring of hell, closest to Purgatory. But the Mark which Dean carries is from Lucifer himself," Cas said. He held his hands out, palms facing Sam as though trying to pacify him. "Dean, I'm afraid, is very close to the Cage where you were held and tortured for so long. Do you realize what going there could mean for you?"

Sam didn't seem to care.

"Cas - less talking – more flying."

"If I do bring you to hell, Sam – there's a very good chance I could only bring one of you back. You could very well be trapped in hell again. Forever."

Sam took a hard step to be right in front of Cas.

"You. Move. Now."

But Dean couldn't let this continue. He stood up from his chair and walked toward the two of them, feeling the muted buzz when he passed through the force field or whatever it was.

"All right, Cas. Stop it."

Sam's eyes widened in surprise and relief when he saw Dean.

"Dean! What happened? What's going on? Cas said you were in hell."

"I didn't tell him to do that, Sam. I didn't know he was going to do it."

Sam turned back to the angel.

"What the hell, Cas?" He demanded. "Why'd you tell me Dean was in hell?"

"To determine your reaction."

"'Determine my reaction'? I'll tell you my reaction, Cas – pissed." Sam stowed the weapons back into his duffel bag. "What did you think my reaction was going to be?"

"This was not for my benefit."

Dean watched Sam's face. He saw the instant Sam realized what Cas meant. His face fell but he didn't look at Dean. He kept his eyes on Cas, "Oh," then scooped up the duffel bag and headed for the bedroom hallway.

"Don't you ever do that again." Dean warned Cas when they were alone again.

"Do what? Demonstrate the lengths to which Sam would go to protect you?"

Dean knew he was skirting – if not downright avoiding – the real issue but he hadn't brought it up so he didn't have to acknowledge it.

"Don't even joke about Sam going back to hell, ever. You understand?"

But all he got back from Cas was the not-surprisingly cryptic, "Do you understand, Dean?" And then he was gone.

Dean thought maybe he should go apologize to Sam for Cas. Or maybe he should leave it alone entirely. He listened to the shower turn on, and could imagine what Sam felt like, taking a shower when not seven minutes before he'd been expecting to have to march on hell. Dean knew he couldn't let that pass without at least checking on Sam.

So, when the shower turned off and he heard Sam head for the kitchen, Dean followed down there, too. He found Sam at the table, eating a bowl of cereal.

"Hey," Sam said, evenly, like it was any regular night and nothing spectacularly shitty had just happened.

"You know," Dean started. "Cas never gave you the code word."

Sam shrugged.

"Seemed like circumstances when you wouldn't have been able to give it to him."

Dean thought very briefly about asking, 'but how could you be sure I wanted saving?' but really – stuck in hell? Yeah, no ambiguity there.

"You were just gonna march on hell?" He asked. Sam turned to look at him and for a moment Dean saw that look, that 'touch my brother at your peril' look.

"March on hell?" Sam asked. "I was going to lay waste to hell." He was done with his cereal and stood up to rinse his bowl and spoon and set them in the strainer. "I'm turning in. I'll see you in the morning."

"Night." Dean said. Maybe the next time he saw Cas, maybe he might just say thanks.

The end.