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.

The firm celebrates as they hit a milestone. Peggy and Paul compete to secure the same account.

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