Over the last few weeks, Mad Men has really been ramping up the dramatic stakes, starting with the now-legendary lawnmower incident and continuing through the firing of closeted-homosexual Sal, forcing its disillusioned characters to confront change at work and in society at large, as we approach with foreboding an historical tragedy—the assassination of President Kennedy on November 22, 1963—that will change the world forever.

In Sunday’s game-changing “The Gypsy and the Hobo” episode, it’s Halloween, and time at last for the masks to come off. If there’s any justice, this is the episode that will earn Jon Hamm his long-deserved Emmy and January Jones at the very least her first nomination. Their confrontation as Betty finally forces Don Draper to shed his carefully constructed façade—while his schoolteacher mistress waits outside, unknowing, in his car!—is the most dramatically charged, emotionally raw work this show has produced in some time. Plus, in other news, Joan whacks her whiny-creepy failed-doctor husband Greg over the head with a vase of flowers in a scene that I’m sure had fans cheering everywhere.

The blows Betty rains upon Don—make that Dick Whitman—are more psychological in nature, and far more devastating. Back early from a family getaway, Betty ambushes Don he prepares to go off on a weekend tryst, with poor Miss Ferrell cooling her heels in the car while Don/Dick is forced to fess up about the life he left behind and the lies he has built his new life and family around. How ironic that mere hours before, in a meeting with the dog-food heiress (a terrific Mary Page Keller) who once was the love of Roger Sterling’s life, Don laid down the law about how her dog-food brand had been irreversibly tainted in a horse-meat scandal: “The name has been poisoned,” he tells her—and she’s not happy to hear it.

Neither is Don happy to learn how poisoned the name of Don Draper now is to Betty, who has seen the divorce papers, the deed to the other Mrs. Draper’s house, the old photos of two boys named “Dick” and “Adam.” Hamm’s performance in this scene is a personal best. Don’s smug, handsome master-of-the-universe look crumbles into that of a lost, stricken, terrified boy: the real Dick. “You didn’t have to look at my things,” he says plaintively. He is shaken, shattered, trapped, and Betty is relentless in her cold, hard, justified anger. “What would you do if you were me? Would you love you?” she asks. His response: “I was surprised that you ever loved me.” But she throws that self-pity right back at him: “Am I supposed to feel sorry for you?” “I don’t know,” he mutters. She rightly calls him out for storing all of this evidence of another life in the house they share, as if he wanted to be found out. She also shows surprising insight into his true character, revealing that she understands that he came from poverty: “I see how you are with money. You don’t understand it.” This entire scene is informed by Betty’s own sense of being trapped, after her family lawyer tells her she has little leverage should she seek a divorce unless she could actually prove adultery. (If only she knew who was lurking outside in Don’s car.)

Act two of this wrenching encounter, which can be seen as the cathartic reconciliation, takes place in the bedroom, as Don/Dick narrates the circumstances of his life as a Whitman as he shows her his long-hidden family pictures. He confesses all, and is wracked with sobs as he gets to the tragedy of his brother Adam, who killed himself after Don rejected him. “I turned him away. He just wanted to be part of my life, and I couldn’t risk all this.” Finally, all defenses lowered, Don breaks down and Betty can now see who this man really is. Does she walk out, or kick him out? The very opposite. The next morning, it looks almost like domestic business as usual, but we know better. The silent stares between husband and wife now speak volumes of understanding as he heads to work, promising to be back in time for trick or treat. And what an artful final scene that is, as Sally (in gypsy garb; she didn’t get that Minnie Mouse outfit she wanted after all) and Bobby (in a hobo outfit, a particularly apt echo of the “Hobo Code” episode that revealed much about Dick Whitman’s youth) hit the streets for Halloween, shadowed by Don and Betty, who’s cradling baby Gene. Knocking on Carlton Hanson’s door, the Drapers’ suburban friend looks beyond the kids at the adults, asking, “And who are you supposed to be?”

Quite the profound question, as the episode fades out on a close-up of Don’s contemplative face. Life, and his treasured family, will go on, but never quite the same.

All of that alone would have made for a spectacular episode. But we also spent quality time with Roger Sterling as he relives his pre-war expatriate youth with Annabelle the dog-food heiress. She sees it as a chance to recapture a romantic Casablanca-style past, but he isn’t buying it. He seems perfectly content with Jane, and tells Annabelle to back off. This is a new Roger, for sure. But still a right bastard at times, as he counters Annabelle’s “You were the one” with a cold retort: “You weren’t.”

Roger is much more accommodating to Joan, who swallows her pride and calls her former boss for help finding work. Their conversation is such a treat. “I like that you thought of me. You know, to ask,” Roger says, beaming over the phone. “You want to be on some people’s minds.” As opposed to Annbelle’s. Sure enough, later on Roger is seen calling a business crony and recommending Joan—“She’s expensive”—for a job that sounds like it will make her paycheck at Sterling Cooper look like chicken feed (or, perhaps, dog food).

And as if smacking her husband with a vase wasn’t enough of an accomplishment for Joan, how about Greg’s epiphany that he can still be a surgeon now that he’s joined the Army. Basic training, here he comes, with Vietnam no doubt to follow. “Please tell me this will make you happy,” he says to his long-suffering spouse. As long as it gets your doofus rapist butt out of the house, yes.

Finally, goodbye to Miss Farrell (I’m sure many will say good riddance), who did the righteous thing and just walked away from the car and the Draper home when Don never came back out to take her away. He calls her the next day from work to say goodbye. “Did you get caught?” Suzanne asks, to which Don answers, “It’s more complicated than that.” (Is it ever.) And to her tearful query, “Are you OK?” his response is pure Don Draper: “Only you would ask about me right now.”

I am continually astounded at the dramatic richness of Mad Men, even as some regular viewers chafe at its perceived slow pace or increasingly dark tone. With only two episodes remaining this season, we’re left wondering how these woefully imperfect characters, and the world of Sterling Cooper (which could be trading hands again in the near uncertain future), will be rocked by the events in Dallas less than a month away.