Betty Draper is more than six months along during this scene. It's taken from the episode "My Old Kentucky Home."
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Peggy has truly arrived as a copy writer. Showing off her new, daring side, she joined the boys in smoking up during a brain-storming session.
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Mad Men Season 3 Episode 3 Quotes

I am so high.

Peggy Olson

I'm Peggy Olson and I wanna smoke some marijuana.

Peggy Olson