"I don't know," Sirius admitted, "I don't know how it works, I just know what's happened - I've been here for - I don't know days now. There isn't a way out of this place." For all that this felt unbelievable to him he could only imagine what it was like for James who was caught up in the middle of his own nightmare that he felt like he had to get back to, no matter what Sirius told him.
"James, listen to me." Sirius said, trying to keep his tone even, to not let the emotion bleed into his words the way he felt it threatening to do. "Look at me." He urged him, because Sirius knew he looked different than he had years ago. "See what I'm telling you," Because he could think of no better way to get it through to his friend without telling him outright what had happened.
"Peter gave you up." He said softly, hating that it was true, knowing what a blow it would be, knowing how heavy that betrayal was. "He betrayed us all," How was he supposed to tell his friend what happened. "That night - he knew what would happen and he gave you up."