"April is the cruelest month, breeding
Lilacs out of the dead land, mixing
Memory and desire, stirring
Dull roots with spring rain."
T.S. Eliot, The Waste Land
The season finale was both dense and satisfying. It did what great fiction is suppose to do: create mirrors of our humanity and inhumanity; layer meanings for depth; excite our senses to want more.
We learn from Marie, Megan's mother, that the setting is in April, when she has come to visit her daughter during Easter, a holiday her husband doesn't celebrate because he's an atheist. Easter, the holy day celebrating the raising of the dead, shows Don in the embryonic stage of becoming reborn, and perhaps not in a good way. We see him helping Megan get a job as an actress in a commercial, playing Beauty in a theme of Beauty and the Beast. Will Don become her Beast? By helping her succeed he may have knowingly helped her to leave to pursue her career, just as he helped Peggy and she left him. We are left with uncertainty when a young woman expresses her interest in him at a bar. He doesn't say he's married. He doesn't say anything. We are left to find out next season.
Phantoms are illusions, transparancies of ideas and ideals but also of the living and the dead. In this episode, Don's waking spirit is not the only apparation we see. Adam, Don's younger brother who also committed suicide by hanging, is seen at SCDP and at the dental office. Adam tells him that his tooth is not the only thing rotten to the core. But this is not Adam speaking: it's Don's conscience.
We also see the specter of Peggy by her absence. When the Topaz client complains about using the word "cheap" in a commercial with a young woman, he mentions that "you should get a girl's opinion. I used to take that as a given here." When Don does see Peggy, it is in a movie theater, home of the shadow world where illusions of human existence are projected in an empty room.
Megan is also shown in this other world light when Don watches her audition reel alone in an ethereal black and white silence: it's as though she is already dead.
Lane's spirit hovers at the company when Harry doesn't want to move into Lane's office and at the partnership meeting when his death benefit to the company makes SCDP profitable for the quarter. Joan also feels guilt over Lane's death, as she thinks that if she had slept with him perhaps he wouldn't have committed suicide. When Don visits Rebecca to offer her $50,000 as reimbursement for Lane's capital investment in the partnership, she accuses him of having "no right to fill that man with ambition." She thinks Don had a corrupting influence on Lane, when she finds the picture of the young woman in his wallet and also the visit to the brothel with the Jaguar client. She believes that ambition was the cause of his suicide, the pursuit of personal achievement which Don embodies.
Pete becomes a ghost before our eyes after Beth's electro-shock treatment erases her memory of him. She further describes his (their) affair as "a temporary bandage on a permanent wound." His physical fight on the train again reminds us of his false pride and self importance. But most importantly, that he is just like Howard but does not have the self awareness to realize it. When the episode ends, Pete is listening to headphones cut off from the world and his family. We don't know what he is listening to as he is no longer there. We can not follow him.
Roger also becomes spirit through his use of LSD again, but this time alone, standing naked, arms open to the world from the heights of a hotel room.
Don's guilt is from his manufactured persona, Lane's and Adam's deaths, his damaged familial relationships. His hard scrabble early life and his own accumulation of bad decisions has been glossed over by a successful career and wrapped in a handsome guy package. His guilt manifests itself in a painful tooth which is infected and needs to be removed. The tooth is a molar. Was it his wisdom tooth that was removed?