Pete Campbell oversteps the mark when he pitches an idea for ad campaign to the head of Bethlehem Steel without telling Don Draper. Draper wants him fired but learns a lesson in corporate politics. Pete's wife wants to buy a Manhattan apartment but he has to approach his cold and distant parents for a loan. Pete's in-laws, however, are more forthcoming.

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.

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.

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.

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.

Joan finds Don the perfect secretary, and Don finds himself in the middle of issues between TV comedian Jimmy and his wife, Bobbie.

Don and Duck try to bury the hatchet, and Peggy attempts to join in on the execs' after-hours meetings. Also, Duck receives a family visit at the office.

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 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.

Don accidentally learns a secret about Salvatore during a business trip to Baltimore. Back at the office, the firings continue, but the new management appoints Peter and Ken as new co-heads of accounts.

Roger Sterling throws an expensive party with his new wife, Joan throws a dinner party, Peggy and Paul get stoned while working on an ad campaign, and Don's daughter Sally steals money from her grandpa.

Don and Betty renew their love affair while on a business trip to Rome, while Peter has a bout of infidelity with an au pair in his building while his wife is away.

As Sterling Cooper prepares for its 40th anniversary party, the bosses in London drop a bombshell to Lane. Miss Farrell's troubled brother pays a visit to her and Don, and Betty stumbles onto her husband's secrets.

On the weekend of the John F. Kennedy assassination, Pete finds out that he lost the promotion to Cosgrove, Roger Sterling's daughter's wedding goes off as planned, and Betty musters up the courage to respond to Don's confessions.

With another sale on the horizon, Sterling, Cooper, and Draper convince Lane Pryce to fire them and then join them as they start up a new advertising firm. At home, Betty follows through with her plans to divorce Don.

Freddy returns with a valuable new client, the firm reluctantly throws a Christmas party for its most important client, and Don prepares for his first Christmas away from his children.

Peter finds out that he will become a father, and has to break some bad business news to his father-in-law. Meanwhile an office focus group study for a client has some unintended personal consequences for Don.

Don deliberately delays returning an important call from California, because he knows it's bad news about Anna. Instead, he keeps himself occupied by forcing Peggy to miss her birthday dinner to pull an all-nighter with him for a client.

Don becomes frightened that his lie will be exposed when government agents question Betty about him, Lane has shocking news for his father when he comes to bring him home, and Joan considers having an abortion.

Don makes a bold, desperate move to save Sterling Cooper Draper Pryce, but the other partners are furious with his actions. Meanwhile, Sally's psychiatrist suggests that she is improving, but Betty is skeptical.

Megan throws Don a surprise birthday party, the war between Pete Campbell and Roger Sterling intensifies, and new mother Joan begins to wonder if she still has a job when she's ready to come back.

Megan is hurt by Don's negative response to the surprise party, Lane finds a missing wallet in a cab, Joan makes an unexpected visit to the office, and Pete makes a play for a bigger office.

While Lane needs some help closing with a potential new client, Peter begins to crack under the pressure of both his home life and work life.

Peter asks Joan to make an unspeakable sacrifice to help secure the Jaguar account, Peggy prepares to make a drastic move in response to Don's treatment, and Megan's acting career begins to create tension with her and Don.

As the partners consider expanding the office space, Don begins seeing ghosts and gets a request to advance Megan's acting career. Meanwhile, Peter's affair comes to a disappointing end, and Megan's mom briefly reunites with Roger.

While Don continues his affair with Sylvia, Pete's latest infidelity threatens his marriage. Meanwhile, Peggy's icy relationship with her new staff continues, but she also gets an unlikely tip on a potential new client.

Don works in secret on a Heinz ketchup campaign while Megan gets a love scene on the set of her soap opera. Meanwhile, Harry makes his power play while Joan has more trouble with the secretaries.

Set among the events surrounding Martin Luther King's assassination, Peggy tries to get a new apartment, Ginsberg is set up on a date, and Don has a revelation during his weekend with the kids.

As the firm prepares to go public, Don and Pete's actions cause them to lose two huge clients. However, Roger uses a new connection to put them in position to gain their biggest client ever.

With his personal and professional life crumbling around him, Don positions himself for a change of scenery. Meanwhile, Pete's life is falling apart as well, thanks to the meddling of Bob Benson.

Peggy has second thoughts about her Burger Chef campaign when Don is asked to pitch her commercial, Pete visits his wife and daughter on his trip back to New York, and Bob Benson gets some surprising news from G.M. about the account.

The partners discover that the firm is losing its independence and there's nothing they can do about it. Peggy is not sure if she wants to come along. Meanwhile, Pete and Trudy have trouble getting their daughter into private school.

Don is stuck in Oklahoma after his car breaks down. Betty discovers that she is not in good health. Pete gets an unexpected job offer that could enable him to get his life with Trudy and his daughter back.

Don's journey ends in California with Anna's niece, Stephanie, where he contemplates his future. Roger decides to marry Megan's mother, Marie. Joan has a business proposition for Peggy, who is coming to terms with her feelings for Stan.

While Don continues his affair with Sylvia, Pete's latest infidelity threatens his marriage. Meanwhile, Peggy's icy relationship with her new staff continues, but she also gets an unlikely tip on a potential new client.

Pete Campbell oversteps the mark when he pitches an idea for ad campaign to the head of Bethlehem Steel without telling Don Draper. Draper wants him fired but learns a lesson in corporate politics. Pete's wife wants to buy a Manhattan apartment but he has to approach his cold and distant parents for a loan. Pete's in-laws, however, are more forthcoming.

Peter finds out that he will become a father, and has to break some bad business news to his father-in-law. Meanwhile an office focus group study for a client has some unintended personal consequences for Don.

While Lane needs some help closing with a potential new client, Peter begins to crack under the pressure of both his home life and work life.

Roger Sterling throws an expensive party with his new wife, Joan throws a dinner party, Peggy and Paul get stoned while working on an ad campaign, and Don's daughter Sally steals money from her grandpa.

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.

As the firm prepares to go public, Don and Pete's actions cause them to lose two huge clients. However, Roger uses a new connection to put them in position to gain their biggest client ever.

On the weekend of the John F. Kennedy assassination, Pete finds out that he lost the promotion to Cosgrove, Roger Sterling's daughter's wedding goes off as planned, and Betty musters up the courage to respond to Don's confessions.

Don is stuck in Oklahoma after his car breaks down. Betty discovers that she is not in good health. Pete gets an unexpected job offer that could enable him to get his life with Trudy and his daughter back.

Don and Betty renew their love affair while on a business trip to Rome, while Peter has a bout of infidelity with an au pair in his building while his wife is away.