Joan Harris paints the office red once again. Photo courtesy of AMC

A show loaded with symbolism, the Sept. 19 episode of "Mad Men" prominently featured three hues -- red, white, and blue -- perhaps as a nod to patriotism during the Vietnam War era portrayed on screen.

While Joan, who's husband is about to serve in Vietnam, ditched her signature reds in episode 8, she now brought them back in full force.

First there was a red, bow-neck, short-sleeved blouse -- a silhouette that keeps popping up on all the ladies at Sterling Cooper Draper Pryce -- tucked into a high-waisted blue skirt (Peggy is seen wearing an almost identical outfit, save for a white blouse featuring a navy bow and matching polka dots).

Later, Joan dresses things up with her blazing-red, curve-hugging dress (seen in the holiday party episode), a red silk blouse tucked into a skirt, and a pink floral-patterned frock that's nipped in at all the right places.

Peggy, on the other hand, is the antithesis of Joan's sex siren persona, and perhaps also a sartorial symbol of the Women's Lib movement bubbling up around her, opting for a more collegiate and unisex approach when she wears a light blue collared shirt, a navy gold-buttoned vest, and a pretty horrendous plaid skirt.

Besides Joan's crimson palette, we were also awestruck by Betty's delicate sky blue, sleeveless dress layered with white eyelets and contrasted with bright red lips. Thank you, Betty. We can always count on you for a swoon.

In related news, learn how to achieve the '60s-inspired beauty looks that popped up on New York's Spring 2011 runways.