On Valentine's Day, the staff of the Sterling Cooper Advertising Agency is hustling and checking out the newest office equipment. Don and Duck clash over an account, and Betty hears from an old friend.
A plane crash causes the firm to go after the account for the airline involved and drop the smaller airline they have an account with. Peggy pays a visit to her mother and sister, who are now guardians of a child.
To show that he has "arrived," Don buys a new car. Pete, Harry and Ken come up with a plan to attract new business, and Don's secretary makes a serious error, which could mean trouble for Joan. Cooper gets a new piece of office art that attracts the interest of the Sterling Cooper staff.
Don and Betty try to keep up appearances as they go to Betty's parents after her dad has a stroke. Peter has a long-dreaded meeting with his mother before he and Kinsey leave for a convention in Los Angeles.
Don blows off the convention in Los Angeles when he meets a beautiful, exotic woman. Back at Sterling Cooper, a member of the creative staff comes out of the closet, and Duck falls off the wagon and initiates his power play.
Don drops off the Sterling Cooper radar and visits the wife of the man whose identity he stole. Back at the office, Bert and Roger consider the merger offer, Peggy makes a play for a real office, and Peter loses his father-in-law's account.
Under the backdrop of the Cuban Missile Crisis, Don returns to New York just as Betty finds out that she is pregnant. Meanwhile, everybody at Sterling Cooper contemplates their futures as news of the merger slowly leaks out.