Roger seeks to expand his affair with Megan's mother. Pete has a "last" encounter with Beth with lasting repercussions. Megan struggles to find acting work and asks for Don's help getting an audition. Peggy still seeks Don's approval.
Lane's shameful secret comes to the surface with dire consequences. Don recaptures his hunger for success, and Sally experiences a major milestone.
Pete asks Joan to make a personal and moral sacrifice to ensure the company lands the Jaguar account. Don becomes furious after learning of the impact Megan's new profession will have on their life. Feeling unappreciated, Peggy attends lunch with Freddy Rumsen, who encourages her to make a move.
Harry finds himself in an uncomfortable position after reconnecting with Paul Kinsey who has joined the Hare Krishnas. Lane takes drastic and unethical measures to get out of financial trouble. Don spends an afternoon with Joan to get her mind off her marital problems.
Don attempts to regain his creative spark, but undermines a member of his staff while doing so. Roger pursues some new clients, and in the process, hurts Jane. Betty displays her pettiness when she reveals a distressing secret to Sally.
Megan leaves SCDP to pursue her acting career; Pete has a fling with his train buddy's wife and then obsesses over her; Don tries to understand the music of the day.
Don is honored at a banquet; Megan saves the day with Heinz; Roger asks Mona for help and begins an affair with Megan's mother. Peggy expects a proposal from Abe but instead moves in with him.
Don abandons Megan at an upstate Howard Johnson's; Peggy fights with Abe and then Heinz; Roger and Jane try LSD but then break up.
The Campbells host a dinner party; Pete tries to make time with a teenage girl; Lane tries to snare Jaguar but ends up coming to blows with Pete.
Don has a murderous dream about a woman from the past; Roger pays Peggy to bail him out with the Mohawk campaign; Greg's military assignment threatens his marriage to Joan.
Betty has a health scare; SCDP gets Mohawk Airlines' business back; Peggy interviews Michael Ginsberg, a brash young copywriter.
Megan's surprise party for Don backfires on her; Joan adjusts to life as a mother; Roger and Pete butt heads; Lane dreams of the woman who owns a wallet he had found; SCDP takes a jab at a rival agency caught pulling a racist prank.