The Other Woman: Joan has decided to accept the partnership. We see her in Pete’s office, and as she rises to leave, we see a detail of her dress that wasn’t obvious at first. The neckline is actually a scarf that comes all the way around the neck and hangs down the back.
Like a noose. Like a noose at the end of the hangman’s rope.
Both women have been strangled by work. Joan has been hung out to dry, she has been condemned, she has been sacrificed–all metaphors that work perfectly with a dress that strangles and hangs her, as if from the gallows.
A scarf around the neck does something else as well—it divides head from body. Both Peggy and Joan have to cut themselves off from what they feel to do what they know is best for them. Both have made a “head” decision that requires a “heart” sacrifice. Both are, therefore, divided at the neck. Peggy has a clear demarcation in the Chaough scene, and later wears a cowl neck when resigning.
Joan hangs herself for Pete and the partners, and then goes to meet Herb bare-necked. He hangs her, and divides her, a second time, with an emerald necklace.
(Credit where credit is due: To Kevin Lee for the awesome screenshots, and to Roberta, for noticing the necklace as a second hanging and the cowl neck on Peggy.)