Pete returns home from his honeymoon excited about his new marriage but conflicted about his past encounter with Peggy.

Don Draper is shaken when his past life comes back to haunt him. After his picture appears in a local newspaper, Adam Whitman, a man who claims to be his younger brother, approaches him. Don, or Dick as his brother knows him, initially denies everything but in the end admits to having taken on a new name. He refuses however to have anything to do with him and tries to buy his silence. When one of the ad men gets a short story published, Pete Campbell is frustrated that his own stories have yet to see the light of day. When his wife approaches an old beau to see if he will publish the stories, he has an interesting proposition for her.

The Agency is looking to land an advertising contract to promote tourism to Israel. Don and his team try to come up with a theme but know so little about the country that they're stumped. So Don calls Rachel Menken to see if she has any ideas. Roger Sterling is getting tired of sneaking around with Joan Holloway and suggests she should get her own apartment but she knows better. Peggy comes up with an advertising concept during a testing session for a new line of lipsticks and she's subsequently asked to write copy.

When Don invites Roger home for dinner, too much alcohol fuels repercussions between Don and Betty and between Don and Roger. Joan puts Roger off for the weekend, spending time with her roommate Carol instead. Pete exchanges a wedding gift for a rifle, and then shares a hunting fantasy with Peggy. Bertram Cooper arranges for the Nixon campaign to meet with him, Roger, Don, and Pete.

Pete Campbell and Peggy Olson start an office romance. Peggy's copy for the lipstick account goes over well and the men in the firm congratulate her. A new telephone receptionist, Lois Saddler, takes a liking to Salvatore Romano but his own interests seem to lie elsewhere. Don Draper gets an unexpected bonus from Bert Cooper and wants to take Midge on a surprise trip to Paris. She seems too involved with her beatnik friends however. Don reflects on his unhappy childhood and in flashbacks he reveals some life lessons he learned early on when a hobo spent the day working on the family farm in exchange for a meal.

Don is courted by Jim Hobart, head of a larger ad firm who offers him more money and more creative resources to join them. Betty Draper rekindles her interest in modeling after Hobart suggests she should try it. She doesn't realize it's all part of the strategy to get Don on board. Peggy Olsen is fretting over her weight gain but doesn't appreciate Joan's advice about getting ahead in the office. The ad team tries to counter the advertising coming out of the Kennedy campaign. Pete Campbell comes up with an idea to keep Kennedy's image off TV in key States.

It's Labor Day weekend and most of the men are sending their wives away for a few days. Don Draper's wife Betty is dreading the thought, as her father and his new girlfriend, whom she detests, will be staying with them. With the election approaching, the team at Sterling Cooper is gloomy since the Nixon campaign has not been following their advice. Roger Sterling was hoping to spend Friday night with Joan Holloway but having just seen the movie Piso de soltero (1960), she is feeling a bit used. She plans a night on the town with her old college friend who has some surprising information for her. Don and Roger invite twin sisters from a casting call to join them for a drink but things go badly for Roger who suffers a serious heart attack. After the incident Don ends up spending the night with Rachel Menken where he reveals a lot of his inner self.

Peggy is given the opportunity to write copy for a new weight loss device that everyone knows is useless. She finds an interesting use for it, however. Afraid of losing the Lucky Strike cigarette account, Bert Cooper gets Roger Sterling to come in for a one-hour meeting but he has another attack. Don Draper becomes a partner and takes over for his friend Roger, but some of the ad men are sharpening their resumes nonetheless. Pete Campbell wants a promotion but Draper doesn't seem too interested. Pete sneaks into Don's office and takes home a parcel sent by Adam addressed to Don that the mail room boy comes to deliver.

Election night arrives and the staff of Sterling Cooper has a party while watching the returns. The election is close and it's obviously going to be a long night. Now a senior partner in the firm, Don Draper must hire a new head of account services, a post that Pete Campbell yearns for. Aware of Draper's secret past, he tries to strong-arm him into giving him the job. With his secret out, Don panics and he asks Rachel Menken to run away with him. Regaining his composure, Don calls Pete's bluff leading to a confrontation with Bert Cooper.

Don and Betty Draper have an argument when it becomes apparent that he doesn't want to spend Thanksgiving with her family and she plans on going only with the children. He also learns some information about his brother Adam. Pete Campbell confirms that he has landed an account from his father-in-law for a new skin care product called Clearasil. He objects however when Don gives the account to Peggy Olson, whom he has just promoted to junior copywriter. Peggy proves her mettle in auditions for the weight loss device but later is feeling unwell and goes to the hospital where she is given some shocking news. Don comes up with a brilliant presentation for Kodak on a new wheel-like storage device for a slide projector that he dubs The Carousel.

Trouble rises on the set of a commercial while Don plays hooky from the office.

Betty becomes suspicious that Don is having an affair after her conversation with Jimmy Barrett, Joan helps out in the television department, and Peggy helps the church with a dance flyer.

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.

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.

Don is brought in to save the day for a P.R. campaign involving the building of the new Madison Square Garden, only to have the rug pulled out from under him. At home, Betty argues with her brother over how to care for their sick father.