Peggy Olsen

What "Seven Twenty Three" is is Don Draper's Waterloo. Or I should say, Dick Whitman's Waterloo. That's the day in 1963 on which Don Draper/Dick Whitman gets lassoed.

Five major plot developments in this episode -- named for the culmination of Betty Draper's pregnancy -- drive the action forward as we enter the middle of the season.

Season 3's third episode, named for a stunning Roger Sterling musical interlude, is as much about tone as advancement of the plot. And a surprisingly musical tone at that.

We learned more about the characters and the changes taking place in this pivotal year. And we tapped into very contemporary themes about corporate disarray and aging parents.

There are a number of ways to view Mad Men. For my own part, I can take it as a period piece, a sort of time capsule of the early '60s, at once relatively close yet far enough away to be intriguing for its unfamiliarity.