Answers abound in season opener of ‘Mad Men’

NEW YORK In retrospect, the bombshell with which “Mad Men” concluded last season was inevitable.

With a busted marriage behind him and a romance in high gear with a self-assured psychologist, Don Draper pulled a fast one in the finale, proposing to his 20-something secretary just days after they first slept together.

This was classic Don. He was seizing what appeared to be a quick fix – the devotion of a sexy younger woman he said “got” him – after he had spent a season lonely and lost and in a tailspin. He needed the recovery, the structure, the renewed sense of identity she seemed able to provide.

“He’s smiling like a fool, like he’s the first man who ever married his secretary,” scoffed one of his ad-agency colleagues in the finale, which was set in October 1965 and aired what seems almost that long ago (though it was actually October 2010).

Now – glorioski! – “Mad Men” begins its fifth season at 9 p.m. March 25 on AMC. Viewers who want to keep the re-entry experience pure are duly warned: Below are a few tiny spoilers.

Many questions will be answered.

For one thing, will Don (series star Jon Hamm) still be linked with Megan (Jessica Pare) – an ooh-la-la French-Canadian who channels the glamour of Jackie Kennedy by way of Jean Shrimpton? And will she still be working at the Manhattan agency Sterling Cooper Draper Pryce, where, in last season’s finale, her engagement instantly sparked awkwardness and resentment from her colleagues?

The two-hour premiere includes a surprise birthday party for Don – a surprise he doesn’t welcome.

Pete (Vincent Kartheiser) has a new home and a baby with his wife, Trudy, but, as usual, he feels undervalued at the office as he manages the bulk of the accounts.

But what about the baby that Joan (Christina Hendricks) was carrying at season’s end? Did she have it, or terminate the pregnancy over worries that her husband isn’t the father?

Roger (John Slattery), the sardonic, gin-soaked agency partner, has a problem: his glad-handing value now seems questionable.

Even hard-working Peggy (Elisabeth Moss) seems to have lost her creative mojo – at least with one client, Heinz, whose baked beans she proposes showing animated in a commercial, dancing into their can.

“You ever see beans up close?” asks the client as he nixes that idea. “They look like a bunch of bloody organs. And it’s not just for fellas like me that saw things in Korea.”

Stiff-upper-lip British partner Lane (Jared Harris) apparently has made peace with lowered expectations for his life. But in the premiere he allows himself a flicker of hope that his life might still take a naughty turn.

The episode is book-ended with glimpses of the civil rights movement, which has spread to a sidewalk in midtown Manhattan. And at Don’s birthday party, arguments arise about the wisdom of the nation’s involvement in Vietnam.

Clearly, things have kept on changing since the start of the “Mad Men” saga, initially set in 1960. It will continue at least two more seasons, fulfilling series creator Matthew Weiner’s original vision of covering that full, tumultuous decade.