In the midst of a crisis, Don runs into an old friend.

Don and Peggy are faced with life-altering decisions

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

Roger pawns off a project on Don, Joan goes on a business trip and Peggy and Pete cannot agree on how to deal with an account.

Don renews his battle with Ted after seeing his relationship with Peggy, Sally interviews at a boarding school, and Pete discovers Bob Benson’s background.

Lane’s shameful secret comes to the surface with dire consequences. Don recaptures his hunger for success, and Sally experiences a major milestone.

Don is honored at a banquet for the American Cancer Society, but finds his professional reputation has been damaged. Sally lends a hand to a relative. Megan’s parents come to…

As Thanksgiving approaches, Don’s work responsibilities interfere with his domestic life. Peggy is given a new opportunity, provoking the ire of some of her colleagues. Betty makes a startling discovery.

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.

Pete’s professional and personal lives become more complicated as he struggles to assert power in both. While facing pressure from his wife regarding a new apartment, he further alienates Don…

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…

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…