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 is tormented as pieces of his secretive past begin to haunt him. Peggy's new success at work, and resulting boost in confidence, threaten her office relationship. Salvatore Romano gets a little too close with a client.

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.

It’s Valentine’s Day, and the Sterling Cooper advertising agency is hustling to stay on top of its game and buzzing over the newest office equipment. Don and Duck find themselves at odds over an account. Betty reconnects with an old friend and once again finds herself struggling with car trouble.

Paul hosts a party at his apartment and introduces someone special to his Sterling Cooper colleagues. Peggy visits her family for dinner. Despite a conflict of interest, the Sterling Cooper agency aggressively pursues an airline account and Duck attempts to appeal to the client using an unorthodox approach.

Trouble arises on the set of a commercial; Harry tries to gather support for a controversial sponsorship; Betty and Don try to appease a client with a friendly dinner.

Don has to deal with issues between a TV comedian and his wife; Joan finds Don the perfect secretary.

Don and Duck try to make peace; Peggy tries to get into the executive's after-hours meetings; Duck deals with a family visit.

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 makes a new friend. Joan meets a client for drinks. Peggy hears impressive new work. Roger has a puzzling phone call.

Sterling Cooper & Partners prepares for a guest; Don contacts an old friend; Roger deals with problems at home; Peggy is underestimated.