A review of tonight's "Mad Men" coming up just as soon as I need a chocolate shake...

"Oh, this car. This thing, gentlemen. What price would we pay? What behavior would we forgive?" -Don

Early in "The Other Woman," Ginsberg is transfixed by the idea of Megan back at the Sterling Cooper Draper Pryce offices, not to help out with the Jaguar campaign, but simply to see her husband.

"She just comes and goes as she pleases, huh?" he asks, simultaneously puzzled and impressed by this woman who to him has a freedom that so many of them lack.

But as the episode moves along, we see that Megan isn't free — that Don's desire to see her only succeed if it's on his terms will hold her back — and that while Don has been fearing that the woman he loves the most (Megan) might run away, instead it's the woman he trusts the most (Peggy) who does it by taking a job at Teddy Chow-guh-guh's agency, while the woman he respects the most (Joan) disappoints him by prostituting herself to a Jaguar exec to help land the account and get a partnership stake in the agency.

It's an hour about women being viewed as a commodity to be bought and sold, or simply owned, spelled out bluntly, horrifically and yet beautifully by Don delivering Ginsberg's "At last: something beautiful you can truly own" tagline just after we've seen Joan slipping uncomfortably out of the Jaguar exec's bed. Herb from Jaguar thinks he can sell his vote for a night with Joan, and the partners think her body is worth 5 percent of the company. When Megan goes for her callback, she's asked to turn around like a piece of meat (or a beautiful sports car) to be inspected. And when Peggy objects to being passed over for Ginsberg on an account she just salvaged with a brilliant bit of improvisation, Don — who once reminded Peggy of what he thinks the money is for — literally throws cash at her to shut her up.

But Peggy doesn't take Don's money then, nor does she when he tries to keep her by his side by topping Teddy's offer. When Don tries to ask for a number, she says there is no number, whereas when Pete tries to pimp out Joan, she simply tells him she costs more than he could afford, then agrees when Lane comes up with a reward she can stomach.

It's reminiscent of the old joke (which I've seen alternately credited to Winston Churchill and George Bernard Shaw) about the man who offers a woman a million pounds for sex, which she accepts. He then changes his offer to a single pound, and she's offended and asks what he thinks she is, to which he replies that they've already established what she is, and are now haggling over the price.

Peggy's refusal to budge — to put a price on her dignity and her independence and her belief in herself — leads to the professional break-up we've feared for a long time, and yet one that was inevitable sooner or later. And it leads to an unsurprisingly fantastic scene between Jon Hamm and Elisabeth Moss, as Don — reeling from what he just learned about Joan, and about the Jaguar pitch — initially assumes it's a negotiating ploy. It isn't — though Don can't help being a jackass even as he thinks it's a negotiation with the "Let's pretend I'm not responsible for every single good thing that's ever happened to you" line — and Peggy says she's going, and going to his hated rival, at that. And all Don can do is kiss her hand as an expression for all he feels about her — a gesture that starts out sweet and then begins to feel sad and lonely and desperate as he doesn't let go — and Peggy again improvises the perfect line for the moment at hand by telling him, "Don't be a stranger."

And lord, do I hope that Matt Weiner means that, because I don't think I can deal with Peggy being sent off to limbo to hang out with Sal and Hare Krishna Paul. We've followed Megan since she left the agency, but only because she's Don's wife. Does the show have time for, and interest in, setting up a parallel narrative at Teddy's shop? It had better, because even though Moss hasn't been quite as consistently prominent this season as she was last year, Peggy has long since become the series' second most-important character. Once upon a time, she was our point of entry into the world of Madison Avenue; now, she's our bellwether of the changing times, continuing to rise even as Don mostly stagnates. The show needs her, not only because of what her experience says about the period, but because she's such a rich character.

But if she's not gone from the show (I hope), she at least gets the perfect exit from SCDP, first with that goodbye scene in Don's office, and then in the way she calmly and quietly gathers the few things she cares about even as the rest of the staff is busy celebrating the Jaguar deal. Only Don knows she's leaving, and only Joan notices she's walking away from the party, but that's okay. Peggy liked these people, but the work is ultimately what drove her, and that's something she'll be able to keep doing at a new agency. She stands in the lobby, alone and looking wistful about all the things she's been through since Joan put her on Don's desk at the start of the decade, but it's not a look of regret. And right before we cut to black, Peggy flashes a confident smile, and the famous opening chords of The Kinks' "You Really Got Me," and we know that she made the right decision — not for money (though Teddy's paying her handsomely), but because this is what she needs to do at this point in her career, even if it inconveniences both her mentor and the guy who created "Mad Men."

Joan's story was trickier, and how you feel about it — and about "The Other Woman" as a whole — depends largely on how much you believe that the characters involved would do what they did.

I believe Pete is amoral enough to pimp out Joan for a client — he was, after all, willing to send his wife out to flirt with an ex-boyfriend just to get one of his short stories published, and that was his wife. And I believe that Dick Whitman, who was never allowed to forget what his mother did for a living, would blanch at the idea of pimping out a woman(*) to a client, particularly a woman he admires as much as he does Joan.

(*) Although I can't help think of how Sal got fired by the agency back in season 3's "Wee Small Hours" for refusing to sleep with Lee Garner Jr. At the time, Don — admittedly in a very dark place in that episode, feeling powerless and lashing out at someone even more vulnerable — essentially tells Sal he should have just had sex with the agency's most important client. When I reviewed that episode, I asked how Don would have reacted had Lee Garner been preying on Peggy instead of Sal. I think we got our answer here, just substituting another woman for whom Don has deep affection and respect. 

The question is whether the other three partners and Joan would go along with it. Would Lane (who also respects Joan, but needs the agency to do well enough to justify his "bonus"), Roger (who has very complicated feelings, but largely protective ones, for Joan) and Bert (who is old-fashioned but also inscrutable) all be so desperate for this client that they would also be willing to play pimp? And would Joan be willing to sell her body at any price?

I don't know, and I imagine I still wouldn't know even if I took days and days with this review. Weiner and co-writer Semi Chellas clearly want us to view it as a desperate situation where the agency's future so rests on this one pitch that the men would be willing to sacrifice Joan's virtue for it. And they want us to see Joan's current circumstances as perhaps not desperate, but difficult enough that a partnership stake in the agency would be worth such a sacrifice. But it feels to me a bridge too far — maybe not as extreme as my friend Linda Holmes, who compared it to the infamous Landry/Tyra plot from the start of "Friday Night Lights" season 2, but something that so fundamentally changes the way you view a number of major characters, and the show that uses them, that it has to be just about perfect to work, and maybe not even then.

And I do think the execution around those four people's motivation was outstanding, particularly the revelation that Don had come to see Joan after she had already sold herself to Herb from Jaguar. Don will never be able to fully enjoy the Jaguar account because he'll never know if it was his delivery of Ginsberg's pitch that got it, or Joan letting Herb unzip her, and show us that scene again with a crucial piece of new information showed us another instance of Don making a sales pitch that was besides the point. I imagine Joan would have gone through with it even had she known earlier that Don was against it — if she's the kind of woman who would do this for her 5 percent, then she would do it even without Don's approval — but from our enhanced point of view, Don never even had a chance.

Again, it comes down to how much you believe. This season of "Mad Men" has been far more overt about each episode's theme than previous years, but has generally been so expert at how it weaves its plot and character in with those themes that it hasn't mattered. If you buy that the partners would be willing to sell Joan, and that Joan would feel the same way, then this is an all-time great episode of the series. But if you don't, then it's Weiner and company making the characters act against their natures to fit the theme.

Me? I don't know yet. But whatever reservations I have about the Joan end of things, those final moments with Peggy could not have been any better, could they?

Some other thoughts:

* Lane manages to protect the agency's cash flow by talking Joan into the partnership versus a payout, but he's still screwed because Bert says the bonuses are a no-go. To be continued...

* I figured Teddy would be back sooner or later, and was pleased to see Freddie Rumsen — who, technically, recognized Peggy's creative gifts even before Don — come back to facilitate the move. Sobriety has been very good to him.

* Joan says that the initial $50,000 offer would be four times her salary, which would set it around $12,500 a year. So Teddy would be paying Peggy a lot more ($19,000) than the pre-partnership Joan to be his copy chief. (And for those who enjoy seeing the numbers adjusted for inflation, her salary would be more than $120,000 in today's dollars.)

* Peggy doesn't keep up her end of the deal by taking Ken with her to Teddy's agency, but now that SCDP has Jaguar, would he be in such a hurry to bolt?

* Getting back to the idea of the men in this episode trying, and sometimes succeeding, at controlling the women in their lives, we see Pete demanding that Trudy let him get an apartment in the city like Howard's. The problem is, Trudy assumes that Pete only has a metaphorical other woman in Manhattan, when he's already had a literal affair with Beth.

* I doubt Gary Basaraba was cast as Herb from Jaguar as a specific nod to "Boomtown," but our second view of the Don/Joan scene reminded me of what that show could do at its best with its fractured timeline and multiple points of view.

* The show Megan auditioned for was Jules Feiffer's "Little Murders," and she's probably better off for not getting cast in the 1967 production, which only ran a handful of performances. The 1969 revival, on the other hand? An enormous hit, and one that was spun off into a 1971 movie starring Elliott Gould and directed by Alan Arkin.

What did everybody else think?

Alan Sepinwall may be reached at sepinwall@hitfix.com