An all-hands meeting is called at Sterling Cooper Draper Pryce, and the gossip starts to fly about an important client leaving the agency and that possibly more will follow. Meanwhile, a competing firm attempts to poach select SCDP employees; Peggy has a passionate romp with Abe and later tries her hand at wooing the Playtex people.

In the Season 4 finale, a surprising opportunity rears its head for both Don and Peggy, leaving them with life-altering decisions to make.