Tom finds out about the affair between Gatsby and Daisy in Chapter 7, just before the three of them, along with Nick, take a trip to New York. Although no one explicitly communicates this fact, Tom picks up on suspicious body language. Specifically, he notices Gatsby and Daisy exchange glances: “Their eyes met, and they stared together at each other, alone in space.” Nick watches Tom as he, in turn, watches the exchange between his wife and Gatsby. Nick writes: “She had told [Gatsby] that she loved him, and Tom Buchanan saw. He was astounded.” Even though Tom realizes the nature of Gatsby and Daisy’s relationship early in Chapter 7, he does not confront Gatsby until later in the chapter, in a room at the Plaza Hotel. Nevertheless, the moment Tom sees what’s going on marks the beginning of the end.