The episode 's finale is Don 's day and the trip to Plattsburgh and Howard Johnson 's Restaurant and Motor Lodge . As he and Megan eat in the restaurant , Megan express her frustration at having her needs and desires take a back seat to Don 's . The discussion escalate into a fight , during which Megan make a hurtful remark about Don 's mother , and Don storm out and drive off without her . Don return sometime later and begin to worry when he can 't find Megan . He spend hours looking for and waiting for her , calling Peggy ( the other side of the conversation from the first part of the episode ) as well as Megan 's mother in Montreal .