One great period piece deserves another, I suppose, so give credit to HBO for promoting its new series, “Boardwalk Empire,” during AMC’s “Mad Men.”

There’s nothing new about that — channels buy spots on each other all the time — but the “Boardwalk” ad touted a rebroadcast of the Sunday premiere that was airing later in the evening.

Translation: When you finish watching “Mad Men” — created by Matthew Weiner, an alumnus of “The Sopranos” — come see what another former member of that writing staff, Terence Winter, is up to. Clever.

Bettydraper Beyond that, it was an especially smashing “Mad Men” episode, with a couple of great scenes devoted to one of the most tragic characters currently on TV, Don and Betty Draper’s woefully unhappy and confused daughter, Sally. If Betty (played by January Jones) was the show’s epitome in earlier years — a beautiful veneer hiding sadness, longing and a trapped feeling — Sally is clearly the symbol for the waves of angst Baby Boomers will experience (and blame on their parents) in their adult years.

Plus, on a lighter note, there was an absolutely riotous interlude (spoiler alert) involving Don’s elderly secretary, Mrs. Blankenship, though I have to confess, I’m going to miss that character terribly. And the payoff was actually rather poignant.

It will be interesting, meanwhile, to see how “Boardwalk” fares ratings-wise in its debut, but given the glowing reviews — rated a hefty 88 by the folks at Metacritic.com — the show already qualifies as a “win” for HBO, which is one reason why broadcasters and even basic cable have cause to envy the pay channel, where buzz is its own form of currency.