It's been a year and a half since Mad Men was last on air, so it's understandable that you may have forgotten some of the details. Don't worry, we're here for you.

Here are the major plot points you should remember before heading into Mad Men Season 5:

Don got engaged: If you don't remember this particular detail, we're betting it's because you scrubbed it from your brain. Unfortunately, now is the time to bring it back to the forefront of your mind. Don (Jon Hamm) did, in fact, get engaged to his secretary, Megan (Jessica Pare), after a whirlwind trip to California. Yes, even though he barely knows her. Yes, even though he had been seeing the strong-willed and awesome Dr. Faye Miller (Cara Buono). Hey, no one has ever said Don makes wise romantic choices.

Sterling Cooper Draper Pryce lost Lucky Strike: The loss of this huge account was a big blow for the fledgling company, not to mention Roger's (John Slattery) ego.

Peggy is awesome, but overshadowed: Don's big news unsurprisingly overshadowed Peggy's (Elisabeth Moss) latest accomplishment: Landing Topaz, the first new account for the company after losing Lucky Strike. We think it's safe to say that Peggy is not amused at her treatment.

Joan is pregnant, and it's complicated: Joan's (Christina Hendricks) husband is in Vietnam, and she hooked up with Roger once again. And whoops, she got pregnant. At the end of the season she decided to keep the baby, and pass it off as her husband's. Also, she got a promotion, but no pay raise, because that's how they roll at Sterling Cooper Draper Price (to be fair, they do have very little money and had just lost a huge account). 

Betty is miserable, fired Carla: Betty pretty much won worst mother of the year award when she forced the family to move away from their old house basically out of spite and then, oh yeah, fired Carla (Deborah Lacey), the maid who practically raised her children. And then she refused to even write Carla a letter of recommendation, all because she had the gall to let Sally (Kiernan Shipka) say goodbye to Glen (Marten Holden Weiner). 

Also of note: Henry (Christopher Stanley) is starting to think Betty sucks. To quote: "No one is ever on your side, Betty." 

Ken Cosgrove doesn't want to use his personal connections in business: And nobody is pleased about it. 

Mad Men Season 5 premieres on Sunday, March 25 at 9 p.m. ET/PT on AMC.

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