Don continues to conceal his increasingly complicated personal life, even in the face of Roger Sterling's invitation to open up. Meanwhile, Peggy pines for the absent Pete still on his honeymoon while fending off the advances of several of the men of Sterling Cooper.

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.

Don loses an account. Roger, stuck in the city for Labor Day weekend, attempts to cheer him up. Meanwhile, Joan has a night out on the town with her roommate.

Peggy is given a difficult assignment. Roger's work problems provide new opportunities for Don, and Pete grows more frustrated. Betty finds a new outlet for her growing dissatisfaction.

Peggy's family hosts a lunch for their church's new priest; Don and Betty enjoy a weekend together; Freddy and Ken take a client out to lunch; the staff works to prepare for a last minute pitch meeting.

Peggy contributes on a church project; Duck and Don try to create market appeal for a foreign beer brand; Harry recruits assistance to help with the workload in his department.

Freddy Rumsen disappoints his team during a pitch. Pete finds an opportunity at the office to exploit while Don proves his loyalty to an old friend. Betty finds a welcome distraction in Sara Beth.

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.

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.