"It's beautiful here," Rose exclaims as they climb out of the TARDIS.
She only has moments to take everything in because suddenly she hears a very familiar whooshing sound.
"But it...can't be," she says quietly, looking at the Doctor.
He doesn't seem surprised - quite on the contrary, he looks as if he had been expecting this all along. There again is that look in his eyes - the indescribable pain and sadness.
Rose barely has time to contemplate this, because just then a blue police box starts to materialize about a hundred feet away.
She gasps. Its the TARDIS. That can't be possible, she thinks as it becomes more and more visible.
"Doctor, what on earth -," Rose starts, but it is then that someone climbs out of the police box. Someone very familiar - too familiar.
It's the Doctor.
My Doctor, she thinks. He is the man with whom she has had countless adventures, the man whom she knew before this new, strange Doctor showed up. From the sideburns, to the blue suit, to the Converse sneakers poking out from under his long coat, he is so very much her Doctor.
Before she can think of what she is doing, Rose starts running towards him. She crosses the distance in mere seconds. She jumps into his arms. In less than a moment, their lips meet.
"I've missed you so much," she whispers in his ear,.
"I've missed you too," he says smiling down at her. With her Doctor's smile.
"But who's that over there? And is that another TARDIS?"
It is then that Rose remembers the other Doctor.
He has been watching them all along. He has known that this would happen - ever since he had started traveling through time and space with Rose again, time had started to rewrite itself. His memories were changing. The moment Rose asked to go to Vienna, he had known.
He couldn't interfere with his own time stream. Both versions of himself being here at the same time was causing a paradox that could rip a whole in the universe. The younger version of him could never know who he truly was, or else the whole of time could cease to exist.
He couldn't stay. And if Rose were to continue traveling with him - the older him, to be exact - she wouldn't be able to stay either.
Rose has to make a choice, and the Doctor already knows what it will be. He remembers.
As Rose sees him close door, she runs back to him, but the TARDIS is already disappearing. Still, she runs. Within moments, it is gone.
As she turns around, she sees her Doctor coming towards her, a confused expression on his face.
"Are you alright?" he asks, his face full of concern.
She chokes on the tears rolling down her face, unable to speak.
"Who was that man?" he asks as he wraps his arms around her.
After several moments, Rose looks into his eyes.
Her voice shaking, she answers.
"Nobody."