A review of tonight's "Mad Men" coming up just as soon as I start with the whole world and eventually check my apartment...

"They didn't know it would be worse than that. They didn't know what was in store for them." -Paulina

Much of "Mystery Date" takes place over a very long, very dark night for the staff of Sterling Cooper Draper Pryce and their loved ones, a night full of nightmares and self-realizations and even more horrifying imagery than last week's introduction of Fat Betty.

In one of the opening scenes, Peggy, Stan and Michael are hanging around the SCDP creative lounge, Stan with a pair of nylons on his head as they work through a Topaz pitch. It's a gag, and a test of how transparent the stockings are supposed to be, but it's also a classic image of what a mugger or rapist might wear, and it segues nicely into the arrival of Peggy's pal Joyce with photos from the Richard Speck massacre in Chicago. "American Horror Story" did a riff on the Speck killings in one of its early episodes, and here "Mad Men" uses the event as a springboard for a series of nightmares, including a very literal one for Don and metaphorical ones for Joan and Peggy. (Sally refuses to sleep to avoid the nightmares, then takes a pill — what I fear will the first of many — to knock herself out.)

When we met Don, he was a philanderer, though we didn't quite know it at first, as he spent several scenes in the "Mad Men" pilot with Midge before finally going home to Betty and the kids in Ossining at the episode's end. And as much as the show has demonized Betty over the years, it's never exactly let Don off the hook for his adultery. He didn't sleep with Midge, and Rachel, and Bobbi, and Joy, and Miss Farrell, etc. just because Betty was an unsatisfactory wife. He slept with them — and, as implied by Bobbi and spelled out by the appearance of Andrea (who, judging by the timeline, would've been on Don's radar shortly before the series began), many more women — because there's something very broken inside him. And Don knows this. He knows this and fears this part of him, even as he's convinced himself that things will be better this time — that Megan Calvet Draper is all the woman he will ever need for the rest of his life.

And he has a literal fever dream in which Andrea somehow shows up at his apartment, then in his bedroom, until he can't resist both her charms and his own weakness. So he beds her and, when she warns him he'll keep making this mistake, he strangles her to death(*), then shoves her body under the bed. It's at once an inverse of the Speck massacre — a dead woman under a bed instead of a live one — a "Wizard of Oz" riff and the realization of Michael Ginsberg's take on the Cinderella fairytale (which also involved a woman in terror with one shoe off and one shoe on). And then Megan appears to him for real in the morning, bathed in a heavenly white light, the angel sent to rescue him from his own demons. But as much as Don insists she has nothing to worry about with him, is he really cured, or will those impulses pop up again in real-life circumstances?

(*) With Jon Hamm in that sequence looking very much like the Red Hulk.

I'm curious when each of you figured out that Andrea's presence in the apartment was a dream. For me, it was the seduction scene, not just because it seemed far too long had passed for Megan to not be home, but because it seemed so blatantly a fantasy/nightmare come to life. And I'm glad it did, because the only way the strangulation scene would have been acceptable to me was with the understanding going in that it was a dream. Had the show not telegraphed that — or had I not figured it out — and Don woke up the next morning with no corpse on the floor, I'd have been irked. That's not a game "Mad Men" should be playing, and one that I'm assuming it wasn't.

While Don was having a real nightmare and Sally was cowering in fear in Henry and Betty's haunted house (a place so creepy that even Paulina complains about the atmosphere), Joan and Peggy were being confronted with more abstract, but no less painful, fears.

Peggy spends a late night working on a Mohawk pitch for Roger before being startled by a noise elsewhere in the office. Though bad things have happened in Peggy's workplace before — including an incident that's finally dealt with in the Joan story — neither the old office nor this one has ever felt like a particularly scary place. But as Peggy moves through the dark, empty space, it suddenly feels like she's the heroine in a horror movie (or the Cinderella of Michael's pitch) before she opens the door to Don's office and discovers the sound was only Dawn, crashing on her boss' couch because there's a certain point in the evening after which it's difficult for her to get home to Harlem in such precarious, discriminatory times. And Peggy, full of confidence, cash and a lot of liquor from her earlier dealings with Roger, decides to invite Dawn into her home, and to extend her aura of awesomeness by bonding with her latest successor and offering shelter to SCDP's pioneering black employee. But she's so drunk and focused on her own career arc that Dawn never really gets comfortable in the conversation, and then there's the horrible, inescapable moment when Peggy realizes she's left her purse out in the living room, and that she's not quite as liberal and relaxed around black people as she thought — and, most importantly of all, that Dawn saw all of this instantly, and Peggy has no way to take it back. Moments earlier, she was trying, tentatively, to compare her situation to Dawn's, and in that glance that lasted only seconds but surely felt to Peggy like an eternity, she realized she had become another insider silently judging the new outsider. It's not a terrible crime — it's not even a Roger Sterling-level joke — but it's Peggy, like Don, being confronted with a weakness she doesn't want to admit that she has.

Because of Speck, there's much discussion of people appearing at doors, and what they might do. The man who crosses Joan's threshold should, in theory, be fulfilling a dream for her. It's her husband, back from Vietnam for a long-awaited leave, with less than two months to go before he's back for good. But we know Greg's more nightmare villain than daydream hero. We know that he raped Joan on the floor of Don's office. We know that he's an insecure bully, whom Joan married less out of love than out of expectations. We know that they've tried to make it work, and there have been moments where it has worked a little, but that ultimately he's the pretty face she settled for. But he's hers, and she's counting on him to be home soon and make her life make sense again — to not only help out with the baby (or as much as the average dad in 1966 helped), but to help push away thoughts of Kevin's real father — and instead it turns out he's volunteered to stay in Vietnam even longer than required.

As he admits to Joan — right after violently grabbing her wrist, in a reminder that when Greg Harris feels insecure around his woman, he's not afraid to exert some physical strength to put her in her place — he's a very important man in Vietnam, as opposed to the schmuck whose career in New York evaporated. And to Joan's credit (and my relief), she finally sees that insecurity, and this selfish decision, and this marriage, for the absurd shams that they all are, and she gets the strength to kick him out of her life, hopefully forever. (And the fact that Greg doesn't even bother to look in at the baby he's been told is his son before walking out doesn't speak highly of his investment in the overall family unit.)

When the morning comes, it seems everyone's emerging from their nightmare, and perhaps none more than Joan. Don's bad dream only lasts a night, where Joan is escaping a nightmare she's been living for years, even if she couldn't admit it to herself before now. So while Don is left feeling uncertain about his wandering eye, Peggy is consumed with guilt over the split-second moment with Dawn, and Sally curls up under the couch like the one survivor of the Speck massacre, relying on Seconal to keep her asleep, Joan lies on her bed next to her son and her mother, wide awake and lost in thought but not necessarily unhappy. This isn't the life she planned for, and it's one that will require many adjustments, but at least the bad man won't be crossing her doorstep again for a very long time, if ever.

Some other thoughts:

* Loved the arrival of the accordion player during the tense dinner with Greg's parents, calling back to a similarly awkward moment involving Greg, Joan and an accordion back in season 3.

* Mädchen Amick, who played Andrea, has always had a bit of a retro look to her, so she slid very easily into the 1966 fashions and hairstyle. 

* It gets overshadowed by the bit with the purse, but interesting to hear Peggy admit she's not sure she has it in her to act like a man all the time for the sake of her career. Meanwhile, we see that Michael Ginsberg already has started to move in on Peggy's niche as the SCDP writer who understands women. Overall, I thought this was a much better episode for Michael, and for Ben Feldman, than last week. He's still twitchy and weird and unable to read social cues (if this show was set in 2012, there would've already been discussion of Asperger's), but not nearly as broad and Woody Allen-lite as last week. And I did laugh at him responding to Ken's suggestion that he was just almost fired with a quick, "I don't think you're right about that."

* Last week, I asked for more of Roger and Peggy together. Tonight, I got it, and it was even more marvelous than the last time. It's again a mark of Roger's falling status and Peggy's rising star and confidence that she's able to hustle 400 bucks out of a name partner (and how many times this season are we going to see Roger empty out his money clip to solve a problem with Pete?), and I could've watched her enjoy the power position and count her new money all night. (If the internet doesn't already have a gif of Peggy counting the money, then I don't understand how the internet works. UPDATE: And it turns outdo know how the internet works! )

* In kicking Greg out, Joan brings up the rape, and it's interesting to contrast how hot her anger justifiably burns over that to Paulina turning the memory of her father violently abusing her into a teaching moment to be passed down through the generations.

* Also note the huge generation gap between Paulina and Sally, with Paulina expecting Sally to already be prepping to be an adult. When Paulina was Sally's age, the concept of a teenager as a separate life stage in between childhood and adulthood was many, many decades away.

* Today, New York City boasts of its clean tapwater. In 1966, though, sometimes the pipes creaked and the water came out brown.

* Yes, I know I keep insisting that the reviews won't come until the morning. And I'm going to keep assuming I will fall asleep without finishing one of these weeks, but it hasn't happened yet. All I'm saying is don't expect this kind of speed to last all season — not without a different one of Grandma Paulina's pills, anyway.

What did everybody else think?

Alan Sepinwall may be reached at sepinwall@hitfix.com