He nods, the sadness in his eyes seeming to deepen slightly. "I understand," he says his voice soft and even, "and I never said everything was going to be okay. I know it isn't. I left all of you and it hurt. I'm amazed Fury even cared enough to hunt me down for this mission. There are a dozen scientists who can do what I can do. I know what they need is the Hulk not me."