The next day, Don comes in and hands his coat and hat to Peggy, quizzically responding to her lack of a salutation with "Morning?" Peggy recovers and tells him about a meeting in the conference room, and Don leaves her to look vaguely disapproving.
When Don enters, Roger is blowing smoke up Ken's ass for finishing the story, although it seems out of character for him to care. He adds that the piece wasn't much to his liking, "but I think it showed an uncanny understanding of what most people like." Haaaa ha ha. "You understand sheep, and we need that around here." Roger instructs Joan to run the meeting, and we hear from Ken, Pete, and Don in turn before Peggy enters and interrupts, saying that Don has a visitor. Don's thrilled to get out of the meeting -- until he hears that the man's name is "Adam Whitman." Don's visibly flustered, but pulls himself together enough to "go deal with this." At least that hangover's gone. Presumably.
Out in the reception area, Don sees the man in question with his back to him, and asks, "May I help you?" The guy turns, and he's an unassuming strawberry blonde of about twenty-five who stares at Don with stars in his eyes: "It's you. It's really you." He calls Don "Dick," and when Don claims not to know what he means, Adam gives him the benefit of the doubt and says he knows he's all grown up now, but he's Adam. "Your little brother." He shows Don the picture of him and Roger, presumably the one from Advertising Age Don mentioned earlier, and the show may have managed to sidestep jinxes, but in so doing ran smack into Irony. Don takes his brother outside and tries one more time to deny his former identity, but Adam's ruthless earnestness will not be stopped, and Don eventually agrees to meet Adam for lunch at a nearby coffee shop.
Don walks back to his office with an expression that suggests he fears all eyes are now upon him. He rejoins the meeting, but we hear nothing of the dialogue, much as Don isn't hearing anything either, until Joan asks him if everything's set for the Liberty Capital people. After a long pause, Don tells her yes, and with that, Roger dismisses everyone. Don strides purposefully toward the elevator, observed by Peggy.
Adam's waiting in a booth when Don walks in and joins him. They shake hands and sit back down, and then Don asks what Adam wants from him. Adam can't believe that's all Don has to say to him. "I thought you were dead, and you're right here!" Starting to realize that this isn't going to go well, he stops smiling and asks Don why he did it. "Why did you leave me?" Don drops the charade and says he couldn't go back there. Adam smiles again and says he knew Don wasn't dead -- he saw him in the window hiding in his uniform. (If you're watching this in order and want to avoid spoilers, here's a helpful tip: Don't click on hyperlinks.) He jokingly asks what kind of name "Donald Draper" is, but Don won't play, saying that people change their names. Don asks what happened to "her," and when Adam asks, "Mom?" Don dismissively says she wasn't his mother. "She never let me forget that." That sounds like a painful memory. It's good that when you're in one of the other ninety-nine compartments of your life, you don't have to think about it. Adam says she's dead of stomach cancer, and Don spits, "Good." Adam adds that their Uncle Mack is dead too, and then says that he's too choked up to eat. He heartbreakingly stares at Don for an eternity before asking if Don missed him at all, and whether he did or not, Don answers, "Of course I did." You might think this proves Don has a heart, but the episode ain't over yet.