Pete's Gun will become a Chekhov's Gun
Harry will leave the firm.
The Draper kids will experience Soap Opera Rapid Aging Syndrome if the series lasts past about 1967, possibly before.
Don really is going to write an autobiography.
Don is the guy jumping off the building in the opening credits.
Sterling is the jumper in the credits.
The jumper in the credits is Lane.
Grace Holloway is the daughter of Joan Holloway
Lane Pryce is related to Wesley
Sterling is related to Roger Sterling.
Don and Peggy will hook up
Trudy Campbell will have a miscarriage
The early '70s were/will be lean years for SCDP.
Samsonite=alcoholism for the Mad Men writers.
Megan is not her real name/she is hiding something
The guy falling in the opening sequence is no-one
In Season 5, the cast will go see How to Succeed in Business Without Really TryingThe movie came out in 1967; Season 4 ended in 1965, so Season 5 will start at least half a year later. There's no way they're going to miss out on a Robert Morse Casting Gag.
The company will now be Sterling Campbell Draper PryceWith Bert gone, they don't even have to change the initials. Additionally, Ken Cosgrove and Harry Crane might be added as partners.
Pete and Trudy are Annie Edison's grandparentsPer this Jezebel comment
The silver/red interior '65 Coupe de Ville is Don's last Cadillac, for a while at least.As he gets into his mid-40s in the late '60s he's likely to want something sportier and more youthful, and that '69 or '70 model (Mustang? Corvette? something European?) will be due for replacement right about the same time as the aforementioned 1973 oil crisis.
Don Draper is no creative genius. He gets all his information through time travel.The evidence is abundantly clear. When he still lives with Betty in their family home, when Betty goes into his office to snoop through is drawers, there's a copy of W.E.B. Griffin's book, "The Corps," which wasn't published until 1986. The only way Don could have gotten this book is if he traveled to the future and came back with it.
Ken Cosgrove is Captain Hastings' son.He looks startlingly like Hastings, and has the same forgetable personality as Hastings, and he's of the right age for it. Perhaps Hastings had an illegitimate son somewhere in America in the mid to late '30s, and may or may not have known about him.
Don has crashed more than one car through drunk driving.In the pilot, he drives home in a 1959 Oldsmobile Dynamic 88, and two episodes later he's driving a 1960 Buick Invicta convertible, which he drives for most of the season. Then, in season two, the Dodge Polara shows up, which he crashes halfway through, and replaces it with the Cadillac. Betty, meanwhile, drove a 1957 Ford Country Sedan station wagon from the pilot until season three, when her father dies and leaves her his 1961 Lincoln Continental. So, the reason those cars disappeared without explaination is Don crashed them. The Cadillac is a turning point - it's a symbol that he's 'made' it - which is why it was detailed when he buys it.
Bob Benson is a serial killerThere's nothing that supports this, but there's something creepy about him.
Megan will become pregnant, and then get murdered, by the end of Season 6I speak of course of the Sharon Tate Conspiracy Theory, where Megan has been wearing many outfits Sharon Tate did shortly before her murder.
Bob Benson is a homunculusThat's the reason he's always got that coffee, since his ourobourous tattoo is located on his palm. Or maybe he's actually Envy in his latest disguise. He's decided to investigate SC&P because he thinks Don would make a good candidate for human sacrifice. Of course, the problem is he doesn't realize he's actually Dick Whitman, he thinks he's the real Lieutenant Don Draper who died who was secretly a powerful State Alchemist. When he finds this out he goes on a violent rampage which is how Megan gets murdered.
Bob Benson is a rare male Puella MagiHis wish was to become part of a top Madison Avenue advertising firm, which is why he just appeared out of nowhere. The real reason he's hanging around Joan so much is because Kyubey senses that Joan has magical-girl potential, and Bob is the veteran to help show her the ropes. Also the big event at the end of Season 6 is Bob turning into a witch.
Pete Campbell is going to leave SC&P at the end of Season 6Okay, here's my actually serious theory. I think this is the most likely "bomb that will be dropped" of all the theories floating around right now. We've seen him meet with Duck to "discuss his options." He's clearly dissatisfied, about the name and about everything else, and seems to be the only person from SCDP who realizes what Cutler is trying to do in terms of slowly taking over the firm and filling it with their guys. Who knows, maybe he'll even quit advertising altogether. But he's clearly at a stand-still in his life, and he seems about to do something rash. Him smoking the joint at the end of "A Tale of Two Cities" seems like symbolism in terms of being an act of defiance against the system of SC&P.
Bob Benson is Frank AbagnaleThe timeline fits. He appeared out of nowhere in season 6 and rapidly rose in the ranks of the firm. His entire appearance was nothing less than a Bavarian Fire Drill, and everybody just assumes someone else hired him.
The show is a novel written by Ken Cosgrove.He's an award-winning writer who seems to exist on the periphery of the story, yet seems to know everything. Every character on the show has a transgressive double life. Ken's perceived transgression by the rest of the characters at the office is his writing. When he is found out, he goes from writing science fiction stories under one pen name, to writing stories that more resembled literary fiction. In the final episode, it will turn out that everything we see was written by Ken, with his author's voice being someone sort of on the periphery, like Nick in The Great Gatsby.
People who accuse Weiner of creating Glen as a walk-on for his son have it exactly backwards.He knew all along that he'd want Glen for a few scenes once a season or so. Casting his son who doesn't act in anything else meant he'd have someone who was always available and wouldn't need to find another kid and reintroduce the character with a different actor every time.
Bob Benson is a wolfThe world of Mad Men is not actually the real 1960s but an AU version where a nuclear war breaks out between the US and USSR and the world ends, so Bob Benson is a wolf in disguise who is hanging around Madison Avenue to show people there to Paradise. Pete Campbell is a noble and Bob is pretending to be interested in him in order to keep an eye on him; Pete's mom is, too, and that's why she mysterious disappeared because Bob had to kill he for trying to open an evil version of Paradise. She was just feigning insanity. Also Joan is the Flower Maiden and this is why Bob hangs around her, also why she's so beautiful and every man wants her.
Don Draper is D. B. CooperThis is a very popular one on the Internet. D. B. Cooper—who used the alias of Dan Cooper—famously hijacked a Boeing 727 on a flight from Portland to Seattle in November 1971, successfully got a $200,000 cash ransom, and parachuted into the wilderness, never to be seen again. He is was described as a dark-haired man in his mid-40s, clean-cut, very well-dressed, very polite, of slightly above-average height, and reasonably decent-looking. The similarities to Don are clear—maybe things really go south for him in 1970-71 and he tries to fix things by disappearing again.
The very final story arc will in some (probably major) way feature the Moon LandingThe final season plays in 1969. The show has always interwoven historical events of the time period with its plot and this is just too perfect to be wasted in some obvious "Let's give all our ad campaigns a space theme!" side story.
Paul's Star Trek script eventually became the episode "Let That Be Your Last Battlefield"After moving to Hollywood, Paul actually did try submitting his Star Trek script to the show's production staff. Initially it was tossed aside like the piece of crap that it was, but a year later, with the show in the middle of it's infamous third season and in dire need of stories, the production team dusted off Paul's script, rewrote it to eliminate the Hare Krishna elements and change the aliens into "half-whites" and "half-blacks," and then produced it.
Ken Cosgrove will Escape from New York.Or LA, either works with the show.
The mid-Season 7 finale will be...Don getting fired for real, possibly for undermining Lou Avery.
Ken isn't blind under the eyepatch.That's right, he's pulling the old Solid Snake in MGS4 on us. He was crying from it in Season 6. Who knows what's under that patch.