The TARDIS phone was ringing and never before had it been so quiet in the blue box. The Doctor pulled a lever and stared at the time rotor as Rory held a hand on Amy's shoulder and the pair stood back, looking from him to the phone and back. Neither dared question him. Neither spoke a word. The phone rang a total of twenty seven times. Amy knew this because she counted. There was little else for her to do.
On the first ring, she reached for it only to have the Doctor quickly cover it with his own hand and shake his head at her. "But you always have me answer the phone. Me or Rory." She looked at him questioningly.
"Not this time." His voice was quiet, but Rory who had been leafing through a book he'd bought on their last alien planet stop, picked up a note of tension.
Amy was going to ignore him as he removed his hand from the phone and started fiddling with something on the console that didn't need messing with. She reached for the phone again. Rory quickly looked up and saw a nearly threatening look on the Doctor's face. It was enough to get him clamoring to his feet. He put the book down and stepped over. He placed a hand on Amy's shoulder. "Uh, Amy, maybe we should...Go over here." He gently nudged her back, away from the phone.
Only now did Amy pay much attention to the fact that this was more than an annoyance to the Doctor. It was something bad. Very. Unlike Rory, who picked up the anger and threat to his wife, Amy picked up on something else. Heartache. She could see it. In the devastated look that traced its way across the Doctor's face for the briefest of moments in spite of his best efforts to fight it off.
The ringing finally stopped. Rory let his hand drop from Amy's shoulder. Mostly because she was now moving forward and away from him. He let her go, sensing that things were safe once more. It wasn't that he didn't trust the Doctor. He trusted him with his very life. But it was in his nature to want to try to prove himself to Amy even though he already had with 2000 years of waiting and then some.
Amy moved closer to the Doctor, and bent in front of his face, peering up at him. She saw it. The tear in his eye. He quickly looked away, blinked, and looked back with a clear face. "Do you mind, Pond? I'm busy trying to keep us from flying off of the vortex!" He was back to his old self just that quickly.
But she wasn't going to let him get away with that. "You were crying, or going to anyway. Why didn't you want that phone answered? Was it River again? Are you avoiding her?" Her gently accusing tone was meant as a light tease, but nothing in the Doctor's expression said he was taking anything lightly at the moment.
"No." The sharpness in his tone made Rory flinch, but didn't even make Amy bat an eye.
"Then why didn't you answer it? What are you afraid of, Doctor? You must be avoiding someone!"
"Not at all." He spoke softly now, moving away from her and messing with a dial a little too long. "I'm not avoiding anyone."
"But someone was calling and you didn't answer and they wanted something, so clearly you're avoiding. Are you in denial?"
He wouldn't look up. "Amy, some things are best left alone."
She wouldn't. "You're avoiding someone! You must be!" She tugged on a random lever, making the ship shudder and forcing the Doctor to look up. He moved around and pulled the lever back up, giving her a look. Her stubborn face was glaring right back at him. He sighed loudly and then spoke up softly, his hands clasped. Rory saw they were trembling ever-so-slightly.
"I have a friend. A beautiful, brilliant, wonderful friend. She used to travel with me. She's off saving the Earth with a group of great kids and doing a wonderful job. She always will be. In that time and in that place. Its what she is meant to do. Forever." He tossed a glare at the phone as if it were making some sort of threatening remark. Then he looked back to Amy.
"There are some places even I can't go. I can't...Not ever. That call was beckoning me to come to a point in time that I can never go." He supposed it was Luke. He didn't much care who was on the other end, only what they were calling about.
He sighed again at Amy's confused look. "Don't you see, Amy? If I allow myself to go there, if I enter that point in her time line...There is no more going back. This way I can...I can continue to visit her freely. I don't have to ever say it!" Goodbye. "I can see all possibilities and that phone call was one possibility I won't ever visit. Consider it a Time Lord's privilege." He moved away from her again, punching in new coordinates.
Baffled, Amy looked back at Rory. Rory shrugged his shoulders. Both turned to stare at the Doctor some more. Amy opened her mouth and Rory could see another question bubbling up to the surface. Apparently, so could the Doctor.
The Doctor stopped and pointed at Amy as he approached her, his voice so quiet, Rory had to strain to hear him.
"I've faced the deaths of people I care about, people I've loved. I've caused deaths, deaths to people I care about and love, Amelia. Many times over. I've faced the unbearable pain beyond all measure of reason that people face when they lose everything they think they're meant to live for." He lifted his hand, wagging a finger at her. "But not this one. Give me this one. I've saved all of Time and Space repeatedly. I'm allowed this one." With that he turned back and steered them onward toward their next adventure. As he did so, he thought back. Back to previous adventures he'd had with a young, inquisitive, brave and brilliant dark haired girl named Sarah Jane Smith. He smiled softly. He would have to pay her a visit again soon.