For the Draper family, life has changed. The children must adapt to a new home, a new brother, and a new stepmother. Don seems to have everything a man could want. However, Megan, still employed at the agency, has difficulty interpreting Don's expectations for a sex kitten at home and a prim and proper employee at the office.

Don and Megan work out some of their issues, Roger and Pete butt heads, and Joan has a run-in with a house guest.

Megan has second thoughts about her future at Sterling, Cooper, Draper, Pryce. Peggy lashes out when she's inadvertently put in the uncomfortable position of having to lie. Pete's effort to protect an acquaintance doesn't turn out quite like he expected.

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.

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.