In "The Doorway," Don Draper is reading The Inferno.
Later in the episode, he gets too drunk and throws up at Roger's mother's funeral.
It's really embarrassing. But it's also one of the first cracks in the veneer. The audience is used to seeing Don as someone who's suave, charming, and, above all, able to hold his alcohol. This Don — sweaty and sick — will recur throughout the season as he loses grip on his life.
In "Collaborators," Don flashes back to an early moment of trauma while in bed with Sylvia.
He then gives Sylvia money, as though she's a prostitute.
At the end of the episode, Don can't even enter his own apartment.
Don starts to look visibly sadder: in "To Have and to Hold," he stays in bed while Megan goes off to work.
Later in the episode, he jealously watches Megan do a love scene, then seeks solace with Sylvia.
In "The Flood," Don drinks heavily after the assassination of Martin Luther King Jr.
He uses the riots as an excuse to avoid his responsibilities as a father.
And he's chided by Megan for it. Throughout the episode, he looks like a sad drunk: disheveled hair, blotchy skin, and — once again — that persistent sheen of sweat.
Don is visibly scared when Ted flies them both in "Man with a Plan."
His need for control plays out in his kinky sex games with Sylvia, but she gains the upper hand.
At the end of the episode, he's still in shock, mourning his relationship as Megan mourns Robert F. Kennedy.
Don cannot handle his breakup with Sylvia, and he lurks outside her apartment in "The Crash."
And the discarded cigarettes suggest he's been lurking for a while.
Don begs Sylvia to come back, and when she refuses, he throws the phone against the wall.
And he's getting sick.
His coughing fit exacerbates the physical traits that have been plaguing him all season: He looks like a mess. And it's only going to get worse.
Along with everyone else in the office, Don gets a shot of amphetamines in the ass.
The longer his trip goes on, the worse he looks.
In desperation, he returns to Sylvia's apartment.
Meanwhile, he continues to flash back to his traumatic childhood.
Back in the present, Don is more frantic than ever at work.
Once Don finally makes it to his apartment, he's stunned to find he's been the victim of a home invasion.
And now, at his lowest, he collapses, landing on his face.
Eventually, he makes it to bed, looking worse than ever.
In "The Better Half," Don has sex with Betty.
Eating alone, he sees Betty and Henry together.
Don's separation from Megan continues in "A Tale of Two Cities," when he goes to L.A.
He ends up collapsing on his hotel bed.
Later in the episode, Don attends a Hollywood party where he gets high and hallucinates.
And then Don dies.
Well, almost. He sees himself facedown in the pool, drowning. Is this still part of the hallucination?
Turns out he's really drowning, and Roger has to revive him.
In "Favors," Don manages to sleep with Sylvia again, but Sally catches them in the act.
Don tries to catch up with Sally to no avail.
He's panicked, which is something the audience hasn't really seen from Don Draper before. Compare this Don with the one who stood up to Pete after Pete discovered the truth of Don's identity. And for a man who's always well dressed, there's something especially unnerving about seeing him frantically tucking in his shirt.
In the lobby, Don can barely speak to the doorman.
Later Don returns home hammered.
Things only get worse when Arnold Rosen shows up at the door.
Outside Sally's door, Don pleads with his daughter to listen.
He ends up returning to his room, resigned.
By "The Quality of Mercy," Don is a shell of his former self, reduced to sleeping in the fetal position in a child's bed.
Megan urges Don to slow down and take better care of himself.
She goes on to tell him that he looks terrible, because he does.
When Betty calls Don to talk about Sally, he can't even put up a fight.
And when Megan comes home, Don continues his self-imposed isolation.
At the end of the episode, Peggy confronts Don for his detestable behavior.
Instead, he returns to the fetal position he began the episode in.
In the season finale, "In Care Of," Don continues to drink heavily.
And he winds up spending the night in jail.
The next day he tells Megan what happened, which means finally acknowledging that he has a problem.
He's fully defeated.
At the office, Ted actually makes Don drink to stave off the symptoms of withdrawal.
His hands are shaking.
And finally, as he hits rock bottom, Don breaks down and starts to tell the truth.
Don tells Megan that they can't move to L.A., and she leaves, maybe for good.
At the end of the episode, Don's partners force him to take an indefinite leave of absence.
Don has now lost everything.
