11. "Lady Lazarus" (Season 5, Episode 8)
Don wants to catch up on what the hip kids of 1966 are listening to, so Megan brings him the new Beatles album, Revolver. He drops the needle on "Tomorrow Never Knows," a blast of the future. He hates it. The Sterling Cooper world is a mess: Pete has floor sex with a self-destructive housewife after reading The Crying of Lot 49. (How far did Pete get into that book? Just curious.) Megan dumps a bowl of emotional Cool Whip in Peggy's lap. And Peggy ducks an unwanted phone call by picking up the receiver and yelling, "Pizza House!" It's kind of sweet how after all these years, Peggy is still so terrible at lying.
Best line: "I like the pictures of the earth! I find them to be majestic!"—Harry Crane