Dean freezes with his burger half-way to his mouth. "What did you say?"
He puts it back in its wrapper as his shoulders fall. There's this mix of disappointment and fear welling up in his chest. He'd told Sam not to try to get him out of it. Is he trying to sign his own death warrant? If something goes wrong, Sam's dead and that's not something Dean's allowing.
"After everything I said to you, you're still going behind my freakin' back." He stands, pointing an accusatory finger at Sam. "I can't believe you."