A review of tonight's "Mad Men" coming up just as soon as I make eye contact with hobos...

"Why do they get to decide what's going to happen?" -Pete
"They just do." -Harry

Early in "Lady Lazarus," Don complains to Megan that he has no idea what's happening in pop culture anymore. She reassures him that "No one can keep up; it's always changing." Culturally, it feels like we've seen more change in this season than the four previous, and that rate is only accelerating. The Beatles are starting to move into psychedelia, as evidenced by "Tomorrow Never Knows," the final track on "Revolver" that Don listens to(*) at Megan's urging. In 1960, no one had the first clue that Sal was gay despite his obvious affectations; now, it's understood and accepted (and a source of jokes by Stan and the others) that one of their new clients from Chevalier Blanc plays for the other team. NASA photographs have given the people of Earth their first glimpse of what their planet looks like from space: beautiful and yet fragile and alone in the vast blackness of space. The world is changing constantly, up to and including everyone's image of it.

(*) I had to laugh when I realized Don was actually going to play an actual Beatles song, given that we got an earlier scene about how difficult/expensive it could be to use their music. Times have changed in some ways, but the Fab Four's catalog still doesn't come cheap, and Matt Weiner made sure to let us know in advance what a big deal — and big budgetary sacrifice — it was for the show to bring us this moment.

And perhaps reflecting that accelerated pace, it feels like certain stories are unfolding more briskly than they might have earlier in the series. It took the first Mrs. Draper three seasons to realize she wanted Don out of her house for good; it took her successor only eight episodes to decide she wanted out of Don's office. And Don, having seen what happened when Betty's dreams all withered and died, is smart enough to quickly agree to let her quit.

The problem is that Megan has somehow built up all the power in their relationship, at work and at home. Megan is the one who keeps Don current, and she's the one who keeps him even vaguely engaged at the office. Joan suggests to Peggy that Megan is just another woman like Betty, but Peggy knows that she's more than that to Don. Megan is everything Don has dreamed of: the glamor and easy charm of Betty, the gift and (seeming) passion for creative work of Peggy, and the independent streak of Don's various mistresses. But fulfilling Don's dreams has put her own on hold, and letting her return to them has Don facing a very literal abyss: the very first thing that happens after Megan leaves the office for good is Don nearly stepping into an empty elevator shaft. Peggy tries to resume her role as Don's work wife — literally in the Cool Whip pitch — but the chemistry's not the same, Don is distracted, Peggy forgets the tagline, and the Head of Desserts wanders off shaking his head. After that awkward pitch, Don goes home and listens to "Tomorrow Never Knows" on Megan's recommendation, but that song — with its backwards guitar solo, Indian influences and lyrics advising you to "Lay down all thoughts, surrender to the void" — may as well have been crafted on Michael Ginsberg's home planet, for all that it speaks to him. He picks the record needle up and walks sadly towards the empty bedroom, adrift at work again and now at risk of losing his wife to another world he knows little of. Don Draper, master of the universe, is now utterly dependent on a woman he can't control (and doesn't want to) and can't entirely understand.

Pete Campbell, meanwhile, has aspired to be Don Draper in many ways, and has usually failed. But here he also finds himself in a relationship with a woman who resembles his first wife on a superficial level, and where the woman has all the power. Pete thought he was taking advantage of Howard's cheated-upon wife Beth, but it turns out she was taking advantage of him. She knows her husband's sleeping around, and she's feeling some existential despair in the wake of seeing those Earth photos, and sex with another man — particularly a man who rides the train with Howard every day — seems vaguely reassuring to her. But that's all she wants, where Pete wants to turn it into an affair of his own. And just as Pete had trouble understanding or controlling Peggy back in the day, he learns here that he's powerless to hold onto Beth, who's able to make their relationship disappear as easily as rolling down the window erases the heart she drew in the fogged-up window.

The episode takes its title from a Sylvia Plath poem rife with Holocaust imagery, about a woman who specializes in dying but keeps being brought back to life to suffer. She doesn't get to escape. On "Mad Men" this week, Megan is allowed to leave Sterling Cooper Draper Pryce, and Beth avoids becoming Pete Campbell's mistress, but their escapes in turn leave the men in question feeling trapped and confused and alone.

Some other thoughts:

* Alexis Bledel (who played Beth) hasn't done much in the way of high-profile work since "Gilmore Girls" ended — the last thing I saw her in was the "ER" finale — and her stiff performance here (the only thing keeping "Lady Lazarus" from being at quite the level of the last few episodes) was a reminder of why. The less dialogue she has to deliver, the better — which makes it remarkable that she wasn't more problematic for "Gilmore Girls." (That, or it makes Lauren Graham even more impressive in comparison.)

* I have to admit to not even recognizing Dennis Haskins — Principal Belding from "Saved by the Bell," and here the Head of Desserts — until someone pointed it out to me on Twitter.

* It's interesting to see that even as they've become something resembling friends, Peggy and Joan still see the world in a different way. Peggy looks at Megan and feels hopeful about the world and the prospects for women (or, at least, for women like Megan who are good at everything). Joan (whom we know is also good at everything she does) looks at Megan in the same deeply cynical way she looks at almost everyone else.

* Is Roger now trying to play head games with Pete to get back at him for the Mohawk stunt? Or has the clarity he achieved with the LSD made him also recognize that he's perfectly happy doing no work if the agency is going to succeed anyway?

* Just as Megan isn't exactly Betty, or Peggy, the song Ken and Stan pick for the Cheavlier Blanc ad isn't exactly a Beatles song, though it's one they recorded for their legendary audition for Decca Records. It's "September in the Rain," and Shazam tells me this is a version recorded by The Wedgewoods. Note that out-of-touch Don immediately assumes it is The Beatles, while younger man of the moment Ginsberg is horrified by the old-fashioned nature of the song (first published in 1937).

What did everybody else think?

Alan Sepinwall may be reached at sepinwall@hitfix.com

Alan Sepinwall has been reviewing television since the mid-'90s, first for Tony Soprano's hometown paper, The Star-Ledger, and now for HitFix. His new book, "The Revolution Was Televised," about the last 15 years of TV drama, is for sale at Amazon. He can be reached at sepinwall@hitfix.com