Jack, listening idly to the conversation going on, almost chokes on his martini.
"My Queen's enemy, the Doctor. His lovely Dark Lady, Martha."
It takes a few thumps of his fist against his chest to make sure he can breathe properly again. That'd be really embarrassing if he flopped over on the bar. He keeps his glass in hand as he walks over to where the man's sitting.
"Excuse me-- hi, Captain Jack Harkness-- you met the Doctor and Martha?"