Man! What a fantastical moment!! (Is fantastical a word?) After Sark is captured and transported back to the United States, Lauren orchestrates an extraction. Sydney and the gang are able to untangle one of Sark's cell phone conversations in which he says, "Not if I see you first, love." The group is convinced that the person on the other end of that phone call is both the mole and the person that broke Sark out of custody.
Later, in the Rotunda, Jack overhears a conversation between Vaughn and Lauren, in which Lauren states, "Not if I see you first, love." Jack knows! Jack knows who the mole is. Now all he has to do is convince everyone else, even Lauren's father, the Senator.
I love this scene! I completely believe that Jack would pick up on those words, that he would peice the puzzle together. Jack was never a huge fan of Mrs. Reid-Vaughn, so it fit perfectly! I also love Jack's talk with Vaughn about the signs that his wife might be betraying him. Vaughn and Jack don't have the best relationship, but Vaughn respects Jack and begins to pick up on the clues.