When Mad Men made its television debut nearly eight years ago, its storyline seemed straightforward enough: When he’s not creating brilliant advertising campaigns for some of the country’s most successful corporations, a handsome Madison Avenue executive named Don Draper likes to smoke, drink, and cheat on his wife.

But as the series continued, cracks began to show in Don's perfectly chiseled exterior. Who is Dickie Whitman? And where is this house of ill repute in which he was raised? As such, Mad Men took on a much more mysterious tone, one that ultimately led devoted viewers to wonder whether the show had ever been straightforward at all. Or if it they had been hoodwinked, and Mad Men had been some sort of strange 1960s fever dream all along. And so began the onslaught of elaborate fan theories about the rabbit hole that Mad Men just might be (some of them crazy, others entirely plausible).

1. DON DRAPER IS D.B. COOPER.

Image Credit: Frank Ockenfels 3/AMC

On November 24, 1971, a well-dressed man in his mid-forties walked up to the Northwest Orient Airlines ticket counter at Portland International Airport and purchased a one-way ticket to Seattle under the name Dan Cooper. Once on board, he made his way to a seat at the back of the plane, ordered a bourbon and soda, and lit a cigarette … then passed a note to the flight attendant, informing her that he had a bomb. His demands were simple: $200,000 in cash, four parachutes, and a fuel truck awaiting the plane upon its arrival in Seattle. Long story short: after being informed that his demands had been met, the plane landed, refueled, and took off again. Twenty minutes later, Cooper—who would become known as D.B. Cooper because of a simple media miscommunication—parachuted from the plane, ransom money in tow, never to be heard from again.

Could D.B. Cooper—infamous hijacker and all-around man of mystery—and Don Draper be one and the same? The physical description certainly sounds familiar. And considering Don’s association with Bert Cooper and the Sterling Cooper ad agency, the alias would certainly make sense. Which could very well be why this theory has gained so much traction, particularly with Lindsey Green at Medium, who wrote an in-depth breakdown of the reasoning behind the idea, noting that the ending has been hinted at since the very beginning. “There’s always been something in the air with Mad Men, quite literally,” writes Green. “From Mohawk to American, North American Aviation, and Ted’s own little two-seater, airlines and aviation are about as prevalent on the show as aliases and fake identities. Even when Joan was upset after being served divorce papers from Dr. Harris, it was a model airplane she grabbed and threw at the unassuming receptionist as Don stood in the doorway. Mad Men has been telling us how the story ends from the very beginning. It ends on an airplane.”

2. MEGAN DRAPER IS SHARON TATE.

Image Credit: Frank Ockenfels 3/AMC

Of the many theories that have popped up surrounding possible plot lines, one that posits that aspiring actress Megan Draper is Mad Men creator Matthew Weiner’s version of Sharon Tate—and is destined to suffer the same fate—has gathered rampant attention. It all began when some eagle-eyed viewers noticed that in season six, Megan wore a T-shirt that was eerily similar to one worn by Tate. From there, additional “proof” began mounting, including a glimpse of Sally Draper reading Rosemary’s Baby, the book that Tate’s husband Roman Polanski adapted for the big-screen. When asked about the connection, Mad Men costume designer Janie Bryant swore to Yahoo! that the choice of outfit “wasn't about Sharon Tate. It was about Megan just being political. That T-shirt [features] the Vietnam star, and in past shows you know Megan has made reference to not really supporting the Vietnam War.” For his part, Weiner himself told HitFix: “The Sharon Tate thing, you know, it’s so flimsy and thin, and at the same time, I’m like, ‘Wow, that’s a lot of coincidence.’ I don’t know what to tell you. I would like to think that people would know that the show’s striving for historical accuracy that I would not add a person who was not murdered by the Manson family into that murder. So that in itself is the dumbest argument in the world for me.”

3. MEGAN DRAPER IS A GHOST.

Mad Men viewers sure do have a morbid fascination with Megan. Shortly after the show’s creators swore that the younger, shinier Mrs. Draper would not be murdered by Charles Manson, fan theorists took another shot at placing Megan in the afterlife: she's already dead! Mainly, this train of thought seems to have sprung from an episode in which Don nearly drowns at a pool party and, in that space between life and death, sees and is comforted by a hallucination of Megan. As Uproxx explains it: “The wording during [the pool party] sequence is very careful. During the hallucination, in addition to finding out that Megan is pregnant, Don asks, ‘How did you find me?’ Megan responds, ‘But I live here.’ The ‘here’ is not California; it can’t be the party. She’s clearly not actually there, but she could be in the afterlife. A few seconds later, Draper sees a dead Private Dinkins, who says, ‘I heard you were here.’ Again, ‘here’ is in the afterlife.”

4. FORGET MEGAN. IT’S BETTY WHO’S THE GONER.

Image Credit: Frank Ockenfels 3/AMC

After all of the talk about Megan’s (assumed) imminent demise, Esquire posited a new theory in the summer of 2013: that if any of Don’s wives were going to kick the bucket, it would—and should—be Betty. “Think about it,” wrote Jen Chaney. “We already got to see Don and Betty together again this season, which seemed to bring closure to that relationship, for Betty at least. Betty is barely in the show these days, so losing that character makes sense from a narrative efficiency standpoint. If we agree that Don Draper's identity as Don Draper will likely cease to exist this season, it would make complete sense for Betty, the symbol of Don's old life as Don, to be gone.”

5. DON’S GOING TO DIE.

Image Credit: YouTube

Mortality has (obviously) always been a recurring theme in Mad Men. And as with any series that’s readying for its final episodes, viewers are anticipating some sort of finality with their finale. Being that Don Draper is the maddest of the titular Mad Men, his death is the only one that would be meaningful enough to really matter. Viewers have combed through hours of footage to point out bits of imagery that hint at Don’s ultimate demise (including the fact that he chose The Inferno as his Hawaiian beach read). But mostly, people reference a possible harbinger that’s been in front of their faces all along: the series’ iconic opening credits, which feature a faceless man falling out of a window.

6. PETE CAMPBELL WILL FALL OUT OF THAT WINDOW.

Image Credit: Frank Ockenfels 3/AMC

Oh, Pete Campbell. Smug, smarmy Pete Campbell. While plenty of viewers have probably gleefully envisioned an episode in which the whiny, overprivileged up-and-comer who everyone loves to hate says bye-bye to the world, Salon dedicated more than 2400 words to the topic in 2012. “Pete Campbell will take a header out a Time & Life Building window, probably around Thanksgiving on the show. (I’m iffy on the when but feeling solid on the who, what, and where),” declared writer Robin Sayers. “I can argue that I came to this conclusion logically, because I was a sociology of media major in college, focused on film and TV theory and I did intern as a script analyst for the late, great Alan J. Pakula (All the President’s Men, Sophie’s Choice, Klute). Plus, I worked in the T&L Building for nearly a decade, so I know that, indeed, its windows can in fact be ‘opened’ … And now I can only see poor Vincent Kartheiser dropping on that stark poster heralding Season 5, even though the cut of that guy’s jib is more Draper than Dyckman.” Okay, so the details on this one are admittedly dated—but it could still happen. Right?

7. DON IS JEWISH.

This one isn’t so much a fan theory as it is one fan’s theory. In discussing the many hypotheses viewers have put forth, Weiner admitted that he kind of enjoys it. “I have no complaint,” Weiner told HitFix in January. “I don’t care how it’s being watched. I mean, I hate the screen within a screen within a screen watching, but I love that people watch the show.” He then recounted one strange encounter with a fan: “You get in this weird situation the first season where people were like, ‘I know Don Draper’s secret. He’s Jewish.’ And I was like, ‘Did I ever put anything in there that said he wasn’t?’ Because he’s not. I mean, I know that.”

8. IT’S ALL LEADING UP TO MAD WOMEN.

Image Credit: Frank Ockenfels 3/AMC

Don Draper may be the star of Mad Men, but neither he nor his business ventures would have been as successful if it weren’t for the women behind the men—namely, Peggy Olson and Joan Harris. Throughout the series’ seven seasons, we’ve seen each of their characters grow, both in their personal lives and their professional positions. Maybe it’s time they strike out on their own?

In The Hollywood Reporter’s recent oral history of Mad Men, Lionsgate COO Sandra Stern recounted that “when we first started negotiating with AMC, one of the things they wanted was a spinoff. We talked about doing a contemporary one. Given the fact that [Mad Men] ends nearly 50 years ago, most of the characters would be dead. Sally was the one character young enough that you could see her 30 or 40 years later. There was a time we wanted a Peggy spin­off, too, and, a la Better Call Saul, a minor character going off to L.A. Matt wasn't comfortable committing to a spinoff.” Which doesn’t necessarily mean it won’t happen. Even if Christina Hendricks, a.k.a. Joan, hasn’t heard anything about it yet.

Earlier this week, the Huffington Post asked Hendricks about the rumors of a Peggy and Joan spinoff. “You're the first I'm hearing it from. It hasn't reached my ears yet,” she replied. Then added: “That would be amazing. If they wanted me, I'd be there.” (Are you listening, Matthew Weiner?)