Spoiler alert: Do not read until you’ve watched tonight’s episode of “Mad Men.”

It’s transition time for the Sterling Cooper team in “Mad Men” episode 712, titled “Lost Horizon,” who finds that their move to McCann-Erickson is not going particularly well. “It’s been a little bumpy,” says Joan, which is more than an understatement.

Don Draper keeps getting lost (so much so that his secretary meets him at the elevator in the morning), Peggy doesn’t even have an office (the new bosses think she’s a secretary), and Joan’s forced to deal with the sexist account executive from McCann who taunted her so mercilessly back in the season premiere. And Roger holds out until the last possible second, using every excuse to pack up his “personal items” at Sterling Cooper before showing up at the new digs.

When Joan last set foot at McCann at that infamous meeting, she told Peggy, “I want to burn this place down” – and by episode’s end, she did her best. First, she has to endure a botched transition sales call with that account exec Dennis, who didn’t bother to read her prep notes — and asks the wheelchair-bound client for a round of golf. “I thought you were going to be fun,” complains Dennis, when she scolds him. And when she tries to get him taken off her accounts, she gets an indecent proposal from the insufferable Ferg — a wolf in sheep’s clothing. “I’m not expecting anything more than a good time,” he says.

Encouraged by her boyfriend, Richard, to treat her work problems as a business deal — and reluctant to walk away from her $500,000 stake in the company — Joan then goes above Ferg’s head, too. But Jim Hobart makes clear that he does not take her seriously. So her negotiation with him, which starts with her asking to run her accounts alone, ends with her threatening to, well, burn the place down with the ACLU and Betty Friedan at her side. To her credit, she keeps her cool — sitting while he stands, firing back with ready responses. “I wonder how many women around here would like to speak to a lawyer”; “I’m sure I’ll find it difficult to find a reporter who wants to embarrass you this deeply.”

Yet, though she turns down his offer of 50 cents on the dollar in the moment, she ultimately is forced to accept it when it’s Roger who presents it. “You started something that can leave you with nothing,” he says. And with that, she picks up the photo of her son, her Rolodex — and walks out. Here’s hoping she can unite that welcome wagon of women behind her.

Don, too, doesn’t last very long at McCann. Though Hobart and Ferg give him the big sell — “You’re my white whale,” raves Hobart — Don’s clearly unsettled about everything he finds in the new office, from his whistling window to the “shirtsleeves operation” Ferg is so proud of. But it’s the crowded pitch meeting for Miller Lite beer that puts him over the edge, as he grabs his boxed lunch and heads in search of his own white whale — the elusive waitress Diana Bower.

The highlight of that fruitless road trip was the welcome return, albeit brief, of Bert Cooper (Robert Morse), to offer a bit of insight: “You like to play the stranger,” he tells Don.

Don’s odyssey was indeed pointless, as Diana’s ex-husband and new wife could offer no information on her whereabouts, despite his ridiculous ruse about her winning a refrigerator full of beer. “You’re not the first one to come looking for her,” says the ex-husband. “She’s a tornado leaving a trail of broken bodies behind her.”

Perhaps shamed at last, Don gets back in his car — but not back to NY. He picks up a hitchhiker who’s heading to St. Paul. ”I don’t want to take you out of your way,” he says. “Not a problem,” says Don. Anywhere but home.

And then there’s Peggy. Without an office to move into, she’s haunting the empty halls of SC&P, trying futilely to get work done, spilling coffee on the floor, spinning her wheels. The lights literally go out on her. As soon as she gets the good news that they’ve found her a space at long last, she discovers another SC&P lingerer — Roger, who’s dreading the move. “You should see the floor I’m on. It’s a nursing home,” he tells her.

Their exchange — over a dusty bottle of vermouth, naturally — begins with her desperate to get away from him. But Roger’s looking for an audience, and she’s trapped. “This is more attention than I’ve ever gotten from you,” she says. So she tells him that he has no right to complain, that this is all his fault. “You were supposed to watch out for us.” It’s true, he concedes. “Even if your name is on the door, you should know better than to get attached to some walls.” A smile creeps across her face: “Hopefully I’ll have that problem some day.” Before long, he’s playing the organ as she roller-skating across the empty floor. The bottle of vermouth is empty as well.

Flush with confidence — and armed with Bert Cooper’s obscene artwork, a gift from Roger — she makes a triumphant, if delayed entrance into McCann. At least someone from the SC&P team stands a chance of being happy there.

But the shenanigans of the rest of the Sterling Cooper gang is clearly starting to wear on a frustrated Hobart, who’s not happy that his white whale is MIA. “Are any of you planning to work here or is this the con of the century?” he asks Roger.

Perhaps the truest words were spoken by Shirley at the top of the episode, who said to Roger, by way of explanation of why she wasn’t going to McCann: “Advertising is not a comfortable place for everyone.” Indeed.

A few random points:

  • “Space Oddity”: The choice of closing songs this season has been thought-provoking, as always. But this one especially is ominous. Whither Don?
  • Glad to see in the sneak peek of next episode the return of Kiernan Shipka. We need more Sally.
  • Betty and Freud is a combustible combination. “We can’t get mad at her for being independent,” cautions Betty as she explains Sally’s absence to a disappointed Don.
  • And there’s nothing like a good Harry Crane putdown: “Maybe they can keep track of your hat size. It seems to keep growing.” Thanks, as always, Roger.