Die-hard Mad Men fans may want to brace themselves because apparently anything can happen during Sunday night's finale of the series. Actor John Slattery, who plays Roger Sterling on the show, says that the show's ending is both "unpredictable and totally organic to the story."

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In a new interview with Deadline on Friday, Slattery says that fans of the show might be floored by what they see, but yet it won't be unexpected either.

He said, "I don't think there's anything that people are going to go, 'wait a minute, what?' and yet it's unpredictable. I think it's a great ending."

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Without giving away too much, Slattery does say that the finale is connected to what happened during the first season of the series, which aired back in 2007.

He said, "It's remarkably well connected to the beginning of the series and the whole series as an arc. It just connects the dots of all of it. It's pretty remarkably structured."

The Hollywood actor also opened up about his character and exactly why he was such an important member of the cast and to the Sterling Cooper Draper Price team throughout the years as well.

Sterling explained, "Roger's skill is deal-making, it's managing accounts and managing people and making them feel good and then making the best deal that he can. The best deal on the table is the deal that he puts forth at the beginning of these seven episodes. If they didn't see what's coming it's probably naive of them, but maybe they didn't want to see it."

The Mad Men finale airs on Sunday night on the AMC network.