[private]
[Whoever brought him back left it is what Cas focuses on. There had been that last moment with Dean in the Impala where Cas had, for just a moment, wondered if he'd be powerful enough to make his way back into hell and raise Sam like he had raised Dean once before.]
[Silence on his end as he searches desperately for what he thinks might have happened. He could have done it, he had wanted to, had seen Dean so broken tired and assumed that if anyone could save Sam, it would be him with his newly gifted strength. With God on his side.]
[But Sam's soul had been left behind. With Michael and Lucifer--both of whom had all the time in the world now that they were trapped. He doesn't know what to make of any of this.] I... We should speak in person. [He's trying to keep his voice neutral.] Where are you, Dean?