The word gets caught in his throat, but the Doctor’s mind hurls out the exclamation without consciously making the effort to do so. It’s the telepathic equivalent of an exclamation point, and blood rushes to his extremities, making his fingers and toes tingle with excitement.
Is it him? Is it really? His Jack, his beloved partner, lover, friend... Oh,but if the universe would stop trying to tear them apart, he would be so happy. But the Doctor had found him once before, and when they’d gotten separated again more than a year ago, he never stopped looking. Not this time. He wouldn’t fail him again. The Doctor had scoured the universe, chasing phantom energy readings and dead end trails... and while his hearts grew heavier every day, he never stopped. He couldn’t let himself fear that Jack was dead, really truly, properly dead, no. He was just missing. Somewhere in the big, wide universe, but alive and waiting for his Doctor to find him.
And now, here he was, that unmistakable trench coat and the spike of dark hair. How many times had the Doctor run his fingers through those soft strands? He knew his every atom intimately and would recognize him anywhere.
The Doctor picked up his feet though they felt leaden from surprise and overwhelming hope (and a fear that he was wrong and it wasn’t him), and jogged the short distance between them. He reached out and took Jack’s hand in his own, pulling him around to face him.
“Oh my Gods... it’s you. Gods, it’s really you.”