Pete returns from his honeymoon, excited about his new marriage, but conflicted about his past encounter with Peggy. After his business relationship with Rachel takes an unforeseen turn, Don attends a party which further illuminates his increasing dissatisfaction with his present life.

After Don wins an award, his photo is featured in Advertising Age. Don must deal with the fallout as the photo brings back a past he isnt ready to confront. Ken gets a short story published in The Atlantic Monthly, inciting jealousy among his colleagues and driving Pete to make an unorthodox request of his wife. Peggy overhears a startling conversation in the office and shares the secret with Joan.

A taboo office romance is revealed. At a brainstorming session, Peggy proves to be more than a secretary, opening up new opportunities for her at Sterling Cooper. Meanwhile, Rachel faces her conflicted feelings for Don after he seeks out her advice on a new campaign.

On election night, the Sterling Cooper staff pulls a rowdy all-nighter while watching the returns. Pete's ambitions cause him to directly challenge Don. Don remembers his past as a soldier in the Korean War.

Betty visits her father; Paul's girlfriend tries to convince him to prioritize his duties; Pete's mother disapproves of his and Trudy's idea.

Don's father-in-law pays a visit to his daughter's family. Peggy works hard on a campaign while the firm tries to decide if they will accommodate an unusual request from a client. Elsewhere, Roger plans a wedding.

The writers make an attempt to stave off late-night boredom during a mandatory overtime session. Roger throws a party as Joan and Greg host their own party. Sally has a run-in with Grandpa.

Don and his father-in-law cross paths. Meanwhile, Peggy is in search of a new roommate; and a rich new client is excited to be doing business with the firm.

Sally's behavior causes concern for Don and Betty. Betty has an eye-opening dream that has a strange effect on her. Pete tries to work a new business angle in his dealings.

Sterling Cooper receives a surprise visitor; Sally has been spooked by something (or someone); and Joan receives some shocking news.

Betty tries her hand at local politics. Don is forced into thinking about the future. Peggy receives a luxurious gift.

There is trouble for Don and Sal in giving their clients what they ask for. Meanwhile, Betty hosts a fundraiser.

The firm celebrates as they hit a milestone. Peggy and Paul compete to secure the same account.

A former client makes a return; Betty and her kids go on a trip; and Joan and Greg make plans for their future.

Peggy's taste in men proves questionable. Pete has to make a big decision about his career and a candidate makes a big impression on Don.

Don has a big meeting with Connie about their future relationship. Betty is the beneficiary of some interesting advice and Pete has a serious sit-down with some clients.

Don deals with a trade-paper interview but doesn't want to talk about himself. A manufacturer of a "wholesome" two-piece bathing suit wants to hire the firm but doesn't want anything too risque. Pete and Peggy try to secure more money for the firm.

The agency's Christmas party is nearly spoiled by the late arrival of a surprise and not-so-welcome visitor.

Don takes a trip. Joan has scheduling problems. Don and Lane get to know each other a little better.

An edict from Roger and Lane puts Pete in a personal dilemma.