The story is set in 1960, with the Nixon-Kennedy presidential campaign in the background. The setting is an advertising agency in Manhattan (hence the name "Mad Men," a play on words between ad men and Madison Avenue.) Common themes in the series are smoking cigarettes (everybody smokes, despite the revelation of health risks,) overt sexism (women are little more than playthings for men,) infidelity, and career ambition. The historical accuracy is a strong point for the series, and it's great to see the characters ooh and aah over the latest gadgets that they are trying to advertise (for instance, the Kodak Carousel for slide projectors has one of the characters scratching his head trying to figure out what the hell it's supposed to do.

I haven't seen the 2nd season yet, which I understand just concluded back in October, so no spoilers please!