"It's not as simple as that," Jack said, heavily. "We can't just save him. We've been there, we've seen what happens. I don't know how you think these things work, but in this reality, we can't just run around messing with time."

Jack's voice was getting a tone, so Ianto reached out and lay a hand on his arm. "What Jack's trying to say is that... We can't. What's going to happen is what's supposed to happen, and messing with that...will effectively destroy the fabric of the universe. From the way that I understand it, anyway." He looked to Jack, to confirm this.