_​Mad Men_: Why Does Don See So Many Dead People?

[WARNING: The following story contains spoilers from Sunday's season premiere of AMC's Mad Men. Read at your own risk.]

For a show so grounded in the real world, Mad Mensure has had its share of ghosts.

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In particular, adman Don Draper ( Jon Hamm) seems to be routinely haunted by people from his past. For starters, he saw his father Archibald Whitman (Joseph Culp) during a drunken hallucination in Season 3's "Seven Twenty Three," as Don wrestled with signing a contract.

Then, after a long night of arguing with Peggy ( Elisabeth Moss) and drinking until he puked, in Season 4's "The Suitcase," Don was visited by a vision of Anna Draper (Melinda Page Hamilton), his oldest friend and confidante who had died of cancer 3,000 miles away.

In the wake of Lane Pryce's suicide, Don was haunted in Season 5's appropriately titled "The Phantom," by his half-brother Adam Whitman ( Jay Paulson), who also took his own life and whose most significant appearance came while Don was gassed up at the dentist's office to remove a rotten tooth.

And, most recently, Don's ghosts got a little more entertaining as he watched Bert Cooper ( Robert Morse) sing and dance his way to the other side, complete with a chorus line of secretaries, in Season 7's "Waterloo."

The spectral appearance in Sunday's premiere, however, seems significant. During a one-night stand with one of a seemingly endless string of new partners since Don's marriage to Megan ( Jessica Pare) ended, Don dreams that Rachel Menken Katz (Maggie Siff), Don's mistress from Season 1, is auditioning for the commercial he's currently casting for Wilkinson lotion. The very next day, while trying to reach Rachel to discuss placing another client's product in her department store, Don learns that Rachel died just days before of leukemia.

As a result of the shock, Don spends most of the episode fixated on a diner waitress named Diana ( Elizabeth Reaser), whom Don insists he's met before. After they inevitably hook up in an alley behind the diner (she mistakenly believed Don came to collect on a very generous tip previously left by Roger Sterling), Don eventually explains his fixation and his recent dream.

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"I want you to think very carefully about when you really had that dream because when people die, everything gets mixed up," Diana says. "Maybe you dreamt about her all the time. When someone dies, you just want to make sense out of it, but you can't."

Indeed, while Don might still be lamenting that Rachel was the one that got away all these years later, he most certainly seems like a man trying to make sense of his life. And perhaps Don is asking himself the same question the song that plays twice in this episode asks: "Is that all there is?"

"[Death] is on his mind," creator Matthew Weiner tells TVGuide.com. "[People] may not turn on the TV to think about it, but we're all wrestling with mortality. It is the greatest issue of our life. Why am I here? Who am I? What was the purpose? Is there an afterlife? Is there no afterlife? What will my kids think? Was I here at all? That is the biggest question of life."

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However, Hamm links Don's obsession with death to the most significant turning point in his life: the day he stopped being Dick Whitman on that battlefield in Korea. "Don Draper is already dead," Hamm says. "He watched Don Draper die and took his life. I think [death] is foremost in somebody's mind when they see that happen. What's it going to be like? It's probably terrifying."

Undoubtedly, this gloomy season-opener is likely to inspire much chatter about whether Don will make it out of the series alive. And Weiner wouldn't have it any other way. "[Death] is a big issue in everybody's life," he says. "The great thing about the show is we've been able to investigate the internal part, and I think it's the ultimate stakes. This is not a show with explosions and murders every week. I love Law & Order... but this is a world that's a lot more like what most of us hopefully experience, which is we are shielded from violent crime for the most part. So, what else is there if you're just a person living with regular life?"

For a man as utterly burdened by guilt and deception as Don Draper, the answer is likely to be even more ghosts.

Mad Men airs Sundays at 10/9c on AMC. What do you make of all of Don's spectral visions?

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