At an advertising agency in 1960s Manhattan, the creative director has problems coming up with ideas for a tobacco account and crosses swords with the female head of a large department store that she wants to take in a new retail direction.
Betty sees a specialist about her ongoing physical problems; a managing partner leans on Don to get involved in the Richard Nixon presidential campaign; Peggy gets some unwanted attention from a copy writer.
Pete's return from his honeymoon stirs up conflicted emotions about his bachelor-party dalliance with Peggy; Don and Rachel's business relationship shifts; Betty sets tongues wagging when she invites the neighborhood divorcée to her daughter's birthday party.
Pete oversteps his bounds in dealing with a valuable client, puts his foot in his mouth and gets a lesson from Don in toeing the company line. At home, he gets pressure from his newlywed bride to buy their own apartment unit.
Don wins a prestigious award and gets his face splashed on a prominent industry periodical, which triggers some fallout from his past; Ken gets a short story published in a national monthly magazine, inspiring jealousy among his colleagues.
Peggy offers superb suggestions during a focus-group session, and her ideas are so well received that her future at the agency looks much brighter; Don asks Rachel's advice about an ad campaign for Israeli tourism.
A boys' night out for Roger and Don ends badly as Roger's erratic behavior damages their relationship; Pete encounters problems on the home front as he and his bride continue to adjust to being married.
Don's mysterious past comes back to haunt him; Peggy celebrates her new work success, but not all of her colleagues and co-workers are pleased or impressed; Salvatore's relationship with a client is questioned.
A rival ad agency tries to poach Don from Sterling Cooper, and they involve Betty in their campaign to land him; romantic rivals vie for Peggy's affections. Also, the agency steps up its Nixon presidential campaign in an attempt to counter successful Kennedy promos.
Peggy is assigned a difficult project; Don seizes the opportunity provided by Roger's latest work woes; a frustrated Pete develops more problems at home and in the office; Betty seeks new relief for her mounting frustrations.